Study Resource 2, Philosophy of Science

Objective Knowledge: An Evolutionary Approach By Karl Popper CHAPTER 1: CONJECTURAL KNOWLEDGE- MY SOLUTION OF THE PROBLEM OF INDUCTION Traditional philosophical problem of induction (Tr): What is the justification for the belief that future will be largely like the past? Or perhaps, what is the justification for inductive inferences? Assumptions in Tr: Future will be like the past. There are deductive inferences and rules for drawing inductive inferences. Popper aims at putting forward the problem that he thinks lies behind this formulation. Part 1- The Commonsense Problem of Induction Bucket theory of the mind/commonsense theory of knowledge: “there is nothing in our intellect which has not entered it through the senses”. (First formulated by Parmenides). Sense-experience is fallible but expectations and belief in certain regularities (laws of nature, theories and others) still exist. Why? Common sense problem of induction- Cs: How can these expectations and beliefs have arisen? Commonsense answer- Through repeated observations made in the past. Repeated observations are the genesis (origin) and justification for the expectation and belief. Part 2- Hume’s Two Problems of Induction Two problems raised by Hume: HL: Are we justified in reasoning from repeated instances of which we have experience to other instances (conclusions) of which we have no experience? Hume’s answer: No. No matter how great the number of repetitions is. HPS: Why do all reasonable people expect and believe then, that instances of which they have no experience will conform to those of which they have experience? That is, why do we have expectations in which we have great confidence? Hume’s answer: Because of custom or habit. We are conditioned by repetitions and by mechanism of association of ideas. Part 3- Important Consequences of Hume’s Results Belief in irrationalist epistemology- reason plays minor role in our understanding. Russell: there is no intellectual difference between sanity and insanity, unless we deal with Hume’s problem. Empiricism cannot escape skepticism if induction isn’t rescued. Clash between rationality, empiricism and scientific procedures Part 4- My Way of Approaching the Problem of Induction Hume’s definition of logic as unsatisfactory Hume defines logic as rational mental processes and mentions valid inference. In Popperian terms, the prime characteristic of science is objectivity. Thus, he sees the need to translate all subjective or psychological terms into objective terms. Formalized terminology Belief- explanatory or test statement (singular statements describing observable events) Justification of belief- justification of the claim that a theory is true Instances of which we have no experience- explanatory universal theories Use of solution to HL and its transference as solution of HPS through principle of transference: “what is true in logic is true in psychology” The principle of transference will eliminate Hume’s irrationalism and break clash between logic and psychology. By principle of transference, there is no induction in psychology too, as there is none in logic. Idea of repetition in psychology is like optical illusion. Part 5- The Logical Problem of Induction: Restatement and Solution L1: Can the claim that an explanatory universal theory is true be justified by empirical reasons; that is, by assuming the truth of certain test statements or observation statements (which it may be said, are ‘based on experience’)? Popper’s answer (same as Hume’s): No. No number of true test statements justify that an explanatory universal theory is true. L2: Can the claim that an explanatory universal theory is true or that it is false be justified by empirical reasons; that is, can the assumption of the truth of test statements justify either the claim that a universal theory is true or the claim that it is false? Popper’s answer: Yes, the assumption of truth of test statements sometimes allows us to justify the claim that an explanatory universal theory is false. L3: Can a preference with respect to truth or falsity, for some competing universal theories over others ever be justified by such ‘empirical reasons’? This is the situation where we have several explanatory theories which compete to be solution of some problem of explanation. Once we solve the problem of induction, then only it is possible to differentiate between good and bad scientific theory. Popper’s answer: Yes, sometimes if we are lucky. Test statements may refute some of these theories. We will prefer those whose falsity hasn’t been established. Part 6- Comments on My Solution of the Logical Problem The focus of his solution: The central issue of logical problem of induction is regarding the validity of universal laws “relative to some ‘given’ test statements”. This does not deal with further questions like the validity of the experienced instance itself i.e. how we are to decide whether test statements are true or false. L1 is the objective form of problem of induction. We shift from future singular instances (of which we have no experience) to universal laws or theories. Why? From logical viewpoint, instances are relative to some universal law. We take help of universal theories to move from instances to other instances. To connect problem of induction with universal laws or theories of science, like Russell. When Popper says that it is not possible to move from experienced singular instances to a universal theory, he is saying that all laws or theories should be considered as conjectures, as guesses. This position has been refuted by Gilbert Ryle who believed that there are general established propositions called laws which are not mere conjectures. However, Popper believes that such a position is untenable keeping in mind the nature of scientific revolution. Newton’s theory once Einstein’s was proved to be true; Discovery of deuterium and heavy water by Urey in 1931 Commonsensical examples of inductivists: Sun will rise and set once in 24 hours. Exception- Frozen sea and midnight sun by Pytheas of Marseilles All men are mortal. Exception- bacteria are not bound to die since multiplication by fission is not death. Bread nourishes. Exception- Hume’s case of people eating daily bread dying of ergotism. L2 is mere generalization of L1 and L3 is mere alternative formulation of L2. An answer to Russell’s question: Some of the sayings of lunatics can be refuted by experience (i.e. test statements). Solution in tune with principle of empiricism: Principle of empiricism (weak form): Only ‘experience’ can help us to make up our minds about the truth or falsity of factual statements. Solution to L1, L2 and L3 fall within deductive logic. There is asymmetry between verification and falsification by experience. # Theory of demarcation- problem of finding a criterion by which one can distinguish between statements of empirical science from non-empirical statements. Solution- Principle that a statement is empirical if there are finite conjunctions of singular empirical statements (basic statements or test statements) which contradict it. Part 7- Preference for Theories and the Search for Truth With respect to a set of competing theories (theories offering solution to the same problem), we will use the critical method to choose which theory is to be considered as an explanation for the problem. This refers to the method of trial and elimination of errors, proposing theories and submitting them to the several tests we can design. We involve ourselves in purely deductive logic- within which L1, L2 and L3 were put forward. Any problems which arise regarding the specifics of the method itself when we try to apply the critical method to the practical situations arising in science will be dealt using methodological rules (the rules of critical discussion). Part 8- Theoretical Preference- Theory of Corroboration The ability to test (testability) a theory increases and decreases with its informative content and therefore, with its improbability (in the sense of probability calculus). Thus, the better theory is the more improbable one. Greater the informative content, the greater will be its improbability (because it will fixate on one particular thing/cause as an explanation for the problem), and greater will be its testability (limited test cases). Eg: Problem statement- Under what conditions can life arise on a planet? T1- Condition 1, 2, 3 T2- Condition 1,2,3,4,5,6,7 and 8. (greater informative content) T2 is more improbable because it narrows down which places would actually have these conditions- but also it is more testable. There can be degrees of corroboration which will give us a concise report for evaluating the state of the critical discussion of a theory, with respect to how it solves its problems, its degree of testability, the severity of tests its undergone and the way it has stood up to these tests. Corroboration is thus an evaluating report of the past performance which can be used to compare between two theories with consideration of critical discussion which includes testing up to a certain point of time/empirical evidence. This does not say anything about the future performance or about the ‘reliability’ of a theory. Part 9- Pragmatic Preference Pr1: Upon which theory should we rely for practical action, from rational point of view? Popper- From rational point of view, we should not rely on any theory, for no theory has been shown to be true or can be shown to be true. Pr2: Which theory should we prefer for practical action, from a rational point of view? Popper- We should prefer as basis for action the best-tested theory. There is no absolute reliance. There can be no good reasons for expecting a theory in practice to be a successful choice. Part 10- Background to My Restatement of Hume’s Psychological Problem of Induction Induction- the formation of belief by repetition- is a myth. There is a need for regularity which makes people seek regularities. The need to impose regularities is based on drives or instincts. The regularities we try to impose might be psychologically a priori but not necessarily a priori valid. Thus, expectations can arise even without or before any repetition. Expectations cannot arise in any other way than instinctually because repetition presupposes similarity and similarity presupposes a point of view- a theory. For this reason, Hume’s inductive theory of formation of beliefs could not be true, for logical reasons. Only objective knowledge is criticizable. Subjective knowledge becomes criticizable only when it becomes objective. It becomes objective when we say what we think- even more so when we write it or print it. In using the term ‘expectation’, we refer to settled beliefs. These settled beliefs can be formulated into hypothesis and thus, into statements of form- ‘I believe that..’. All these formulated statements can be considered critically. There can be fanatic acceptance of a belief to tentative acceptance. Part 11: Restatement of the psychological problem of induction PS1: If we look at a theory critically, from point of view of sufficient evidence rather than any pragmatic point of view, do we have a feeling of complete assurance or certainty of its truth, even with respect to the best-tested theories, such as that the sun rises every day. Popper- No. PS2- Are those ‘strong pragmatic beliefs’ (beliefs which have to do with choosing between alternate action) which we all hold such as that there will be a tomorrow, the irrational results of repetition? Popper- No. These beliefs are partly inborn, partly modifications of inborn beliefs resulting from method of trial and error-elimination. There is nothing irrational about pragmatic belief in the results of science. CHAPTER 2: TWO FACES OF COMMON SENSE- AN ARGUMENT FOR COMMONSENSE REALISM AND AGAINST COMMONSENSE THEORY OF KNWOLEDGE Science, philosophy, rational though starts from common sense. Even though common sense is vague and insecure point to start with, we do not aim or try to build a secure system on these foundations. Popper’s first thesis- Our starting point is common sense and our great instrument for progress is criticism. We only need competing theories to have scope for critical or rational discussion. The fundamental problem of theory of knowledge is the clarification and investigation of this process by which our theories may grow or progress. Realism- Realism is essential to common sense. Common-sense distinguishes between appearance and reality. There can be surface reality and depth reality. There are also many sorts of things which can be real: taste and weight of foodstuffs, language, governmental decision, regularities, structures and so on. Popper’s thesis- Realism is neither demonstrable nor refutable. No valid proof of realism can exist. Idealism says that all I experience of the external world is a dream. Even if you do anything to assert your existence, it would just be me dreaming it. Thus idealism cannot be refuted. This also means that realism is not demonstrable because idealism can always put forward arguments to say that the reality being referred to is only a figment of my imagination and thus, reality cannot be demonstrated at all. Realism is not only indemonstrable, it is also irrefutable. There can be no describable event or conceivable experience which can be taken as an effective refutation of realism. Arguments in favor of realism and against idealism: Realism is part of common sense and that all the alleged arguments against realism are not only philosophical in “most derogatory sense of this term’ but are at the same time based upon an uncritically accepted part of the commonsense theory of knowledge, called ‘bucket theory of mind’. Argument from science- Scientific realism: What we attempt in science is to describe and explain reality. We do so with help of conjectural theories- which we hope to be true but which we cannot establish as certain or probable. The procedure adopted in science may lead to success- our conjectural theories tend progressively to come nearer to the truth- to the true descriptions of certain facts or aspects of reality. Argument from language- Human language is essentially descriptive and unambiguous descriptions are always realistic. It is of something- of a state of affairs which may be real or imaginary. In Tarski’s terms, if a state of affairs is imaginary then the description is false and its negation is true description of reality. This may not be completely certain but is a rational argument for realism. Idealism is absurd- It is absurd to believe that my mind creates this beautiful world. Denial of realism amounts to megalomania. If realism is true- then the reason for the impossibility of proving it is obvious because our subjective knowledge- our perceptual knowledge- consists of dispositions to act and thus, a kind of tentative adaptation to reality. Thus, even though we are fallible, there seems no point in truth or falsity of our opinions or theories if there is no reality, only dreams and illusions. Realism is the only sensible hypothesis. Popper supports the commonsense theory of Tarski- that truth is correspondence to facts (or with reality)- a theory is true if and only if it corresponds to the facts. Metalanguage- Truth and falsity are essentially properties, or classes of statements of unambiguously formulated theories or propositions of some language L1 about which we can speak quite freely in another language Lm (meta-language). Phrases of Lm which refer in some way to L1 may be called metalinguistic. We use metalanguage in which we can state the fact about which the statement in question speaks and in addition can also speak about the statement in question. “The phrase P of the object language is a statement corresponding to the facts if and only if p.” – For instance, “The phrase ‘snow is white’ is true if only and only if snow is white”. This is an objectivist or absolutist notion of truth. Verisimilitude- Content, truth content and falsity content Two notions combined to form logical notion of verisimilitude: (a) The notion of truth; (b) The notion of the logical content of a statement (class of all statements logically entailed by it- consequence class). Truth content refers class of all true statements which follow from a given statements (or which belong to a given deductive system) and which are not tautological. The truth content of tautologies is zero. All other statements, including all false statements, have non-zero truth content. Falsity content refers to class of false statements entailed by a statements- the sub-class of its content which consists of exactly all those statements which are false. The verisimilitude of a statement increases with its truth content and decreases with its falsity content. A theory T1 has less verisimilitude than a theory T2 if and only if: Their truth contents and falsity contents are comparable And either: The truth content but not the falsity content of T1 is smaller that of T2; OR The truth content of T1 is not greater than that of T2 but its falsity content is greater. Thus, T2 is nearer to the truth than is T1 if and only if more true statements follow from it but not more false statements or at least equally many true statements but fewer false statements. Theory of corroboration: Content is the quality of a particular theory of hypothesis. A higher level of content leads to higher level of testability. This means that there is greater relative difference in statement from background knowledge (b). The greater the degree of universality or precision corresponds to greater empirical content and therefore, greater degree of testability. Precision refers to level of description that is reached by the prediction of hypothesis. Higher level of precision means finer and finer descriptions of reality. This increases the testability by limiting the number of possible events which are consistent with the theory. Precision is exclusion. Universality refers to the number of classes which are derivable from hypothetical statement. This is the phenomena used to test the hypothesis. Universality is the scope of demands hypothesis makes on reality- this will vary in levels of precision. Universality means inclusion. Degree of corroboration (DoC): The relative tentative confirmation or confidence in one hypothesis over another based on the performance of each hypothesis under critical tests. Popper writes a distinct absolute probability calculus to eliminate contradictions and logical absurdities which arise in using formal probability calculus to assess the support of a hypothesis by evidence. The idea of corroboration is central to empirical science. Scientific knowledge can never be verified, only tentatively accepted. Popper saw corroboration of a theory or hypothesis (h) by evidence (e) as a continuum that ranged in degrees from refutation to independence, or irrelevance to corroboration. Truth and confirmation do not play any role in absolute calculus of corroboration. Truth is atemporal because ‘what is true in the present was true in the past and will be true in the future’ Corroboration is temporal because the outcome of tests is unknown before they are implemented: a particular test may have corroborated a hypothesis yesterday and another more severe test corroborated it today. Most importantly, there might be another test which refutes it tomorrow. Corroboration formula: The corroboration of the evidence (e) given hypothesis (h) is equal to the absolute probability of e given h minus the absolute probability of e alone divided by the absolute probability of e given h minus the absolute probability of h unified with e plus the absolute probability of e alone. Addition of b (background knowledge): The denominator has low significance and can be neglected. The three components of corroboration are: Theory or hypothesis (h) Evidence (e) Background knowledge (b) A test proves its worth by maximizing the value in the numerator with respect to competing hypotheses. Positive value of numerator: The numerator will be positive as the probability of e becomes greater due to h relative to b. {when P (e,hb) is greater than the P (e,b)} Negative value of numerator: The numerator will be negative if the probability of e in light of h is less than that given b alone (this is falsification). {when P (e,b) is greater than the P(e,hb)} Zero value: No corroboration if both probabilities are same and value of numerator is zero. The result is tautology. Corroboration can be accomplished if h is falsifiable (i.e. it must contain testable content different from b) and gives predictions consistent with e (i.e. demands few ad hoc hypotheses to fit the evidence). Bucket theory of mind: This is the commonsensical theory of mind. Our mind is a bucket which is originally empty or more or less so. Material enters into the bucket through our senses and accumulates and gets digested. This is philosophically known as tabula rasa theory of mind- mind as an empty slate upon which senses engrave their messages. Thus, all knowledge consists of information received through our senses- through experience. The following elements of bucket theory of mind are refuted: Knowledge is conceived of as consisting of things or thing-like entities in our bucket. Knowledge is in us- it consists of information which has reached us and which we have managed to absorb. There is immediate or direct knowledge. All errors or mistaken knowledge arise from bad intellectual digestion which adulterates the given elements of information by misinterpreting them or wrongly linking them with other elements. Knowledge is essentially passively received knowledge while error is always actively produced by us either by interfering with the given or by some other mismanagement- a perfect brain cannot err. There is practical need of knowledge of higher level which goes beyond mere data or elements. We connect existing data with impending elements. The higher knowledge establishes itself by association of ideas or elements. Ideas are associated if they occur together- association is strengthened by repetition. In this way, we establish expectations (if idea a is strongly associated with idea b, then occurrence of a arouses high expectation of b). In this way, beliefs also emerge. True belief is belief in an unfailing association. Erroneous belief is belief in an association between ideas which, even though haven’t occurred together, are repeated together generally. This is close to empiricism of Locke, Berkeley and Hume. Criticism of bucket theory of mind: Quest for certainty Primarily, it is engaged in the assumption of quest for certainty. This quest for certainty leads us to assert that there are sense data, immediate experiences, sense impressions which are the basis of all knowledge. However, these elements do not exist at all. Our subjective knowledge of reality consists of maturing innate dispositions. We refer the messages we receive from our environment to the reality- these messages are decoded through a complex process. Those messages which are biologically important for us currently or in the future are preserved, while a majority of them are ignored. We learn to decode theses messages by trial and error elimination. We learn to put the process of decoding in the background such that we receive the decoded messages as given. However, most of the times, there are errors in our receivals which are corrected through complex mechanism. The idea of a ‘given’ of true data, with attached certainty is only a mistaken theory which is part of common sense. Criticism of subjectivist theory of knowledge Subjectivism says that science is the perfect instrument of prediction and does not reveal any standard of truth to us. That there are no higher standards of certainty. Because there can only be subjective use of science as instruments in one’s practical pursuits. There is no objectivity it can claim to. Physiology (physics) says that our ‘data’- scientific is fallible and not the standard of truth or certainty. This means that what is fallible is the data we use to predict (subjective), not the standard of truth or certainty we have. Popper’s rectification of the commonsense theory There is knowledge in the subjective sense, which consists of dispositions and expectations. There is also knowledge in objective sense, human knowledge, which consists in linguistically formulated expectations submitted to critical discussion. Commonsense theory fails to see the difference between the two above points. Subjective knowledge is not subject to criticism. Objective knowledge can change and grow by elimination of linguistically formulated conjecture. Commonsense theory is only a theory of genesis of knowledge- how we acquire knowledge passively. Seen as a theory of growth of knowledge, it is completely false. Evolutionary Epistemology Epistemology as prior to genetics: The logical investigations of questions of validity and approximation to truth are of greatest importance for genetic, historical and psychological investigations. Criticism of idealism: Immediacy or directness of our ideas, impressions or perceptions is the result of our biological outfit which is well-adapted to the environment. However, this immediacy does not establish truth or cannot be criteria for truth. This is the fundamental mistake of idealism. Darwinism There is an environment with certain structure. This is empirical. This environment changes- but not too fast for long period of time and not too radically. This is empirical. Organisms produce mutations over a period of time which allows it to adjust to their environment. This process of adjustment is a trial-and-error-elimination method. This is the logic of situation- the a prior component of Darwinism. How a priori? Evolution can only occur if such a process of adjustment is taking place. Descriptive and argumentative language: Linguistic formulation of theories allows us to criticize and eliminate them without “eliminating the race which carries them” Development of a conscious and systematic attitude of criticism towards our theories. This is the start of the method of science. Method of science is criticial method. Aim of science and All Knowledge is theory-impregnated, including our observations The aim of science is increase of verisimilitude. Every stage in the evolution of life and development of an organism assumes the existence of some knowledge in form of dispositions and expectations. The growth of al knowledge consists in the modification of previous knowledge- either in its alteration or its large-scale projection. Some part of this previous knowledge is taken for granted which conflicts with our observations and hypotheses. There is plasticity in the organism for modifications of this inborn knowledge. Growth of knowledge: All acquired knowledge, all learning, consists of the modification (possibly the rejection) of some form of knowledge or disposition, which was there previously; and in the last instance, of inborn dispositions. All growth of knowledge consists in the improvement of existing knowledge which is changed in the hope of approaching nearer to the truth. All our dispositions are adjustments to the slowly changing environmental conditions- for this reason, they are theory-impregnated (assuming a broad definition of ‘theory’). Knowledge in objective sense: The direct or immediate observational experiences cannot be our starting point. Three worlds: World 1- Physical world World 2- World of our conscious experiences- Subjective knowledge- organismic knowledge Consisting of dispositions of organisms World 3- world of the logical contents of the book, libraries, compute rmemories and so on- Objective knowledge- knowledge in the objective sense Logical content of our theories, conjectures, guesses- logical content of our genetic code. Eg: Theories published in journals and books and stored in libraries; discussions of such theories; difficulties or problems pointed out in connection with such theories and so on. On World 3: Problems in World 3 can be discovered before they are discovered and become conscious of in World 2. World 3 is autonomous in a sense. As we make geographical discovering in world 1, we make theoretical discoveries in world 3. Main thesis- Our conscious subjective knowledge/world 2 depends upon world 3/linguistically formulated theories. Popper says that the full consciousness of the self is dependent upon world 3. We derive our immediate self-consciousness and knowledge of self through theory of body and its continued existence in sleep, theories of time (linearity) and others accessible in world 3. These world 3 elements decide our expectations- of waking up after sleeping tonight. For this reason, Popper points out that “full consciousness of self depends upon all these (world 3) theories” and adds that animals have capacity for feelings, memory, sensations and therefore, of consciousness but they do not possess the full consciousness of self which is the result of human language and development of human world 3. Method of Science: “The method of science is the method of bold conjectures and ingenious and severe attempts to refute them.” Bold conjecture: A theory with a great content- greater than the theory which will be superseded by it. The main verification for increase in verisimilitude is not the increase in truth content alone. For the truth content will increase with the increase in content anyway. The point is to verify if the false content has increased or not. One can never be sure that a theory is completely devoid of increase in false content. We can only search for falsity content of our best theory by trying to refute it- by testing it severely in the light of our objective knowledge. A theory may be false even if it passes all the tests. But if it passes all the tests, then we can conjecture that the theory has greater truth content than its predecessor and may have no greater falsity content. If the theory also stands to the tests in fields where its predecessor had failed, then we can say that the new theory is a better approximation to truth than the old theory. Science: The Growth of Knowledge through Criticism and Inventiveness Science replaces the elimination of error in violent struggle for life by non-violent rational criticism- this allows us to replace killing of world 1 and intimidation of world 2 by impersonal arguments of world 3. Difference between commonsense theory and Popper’s critical standpoint Early philosophers Critical (Popper) 1 Starting point is decisively important. Must not fall into error in the very start. Starting point is not decisively important because it can be criticized and corrected like everything else. 2 Starting point should be true and certain. No way to find such a secure starting point. 3 Found in personal experience of self (subjectivism) or pure description of behavior (objectivism). Not found in either subjectivism or objectivism. Best to start with both and to criticize both. 4 By accepting either subjectivism or objectivism, commonsense theory of knowledge arises. This theory is the weakest point of commonsense. We should start from common sense and be critical of it. 5 We can have the most certain knowledge only about ourselves and our observational or perceptual experiences. All our knowledge is theory-impregnated and all are also conjectural in nature. 6 Our clear and distinct sensations or sense data can be the hard facts on which our knowledge is based. Direct or immediate experiences cannot be false. All knowledge is theory-impregnated. The foundation can be improved by critical method and not taking any data for granted. 7 This is the clear result of commonsense theory of knowledge. Commonsense theory does not look at indirect and conjectural character of knowledge. Our sense organs are also theory-impregnated and open to error. 8 Realism of common sense theory leads to epistemological idealism or operationalism. Even realism and its biological theory of knowledge are two conjectures. Realism is a better conjecture than idealism. 9 Commonsense disproves itself- starting from realism and ending in subjectivism. Commonsense theory is self-contradictory. This does not affect the commonsense theory of world- which is, realism. So, the commonsense theory of world- realism can be preserved while the epistemological commonsense theory (bucket theory of mind) can be given up due to its self-contradictory nature. CHAPTER 3: EPISTEMOLOGY WITHOUT A KNOWING SUBJECT: THEORY OF SCIENTIFIC KNOWLEDGE Part 1: Three Theses on Epistemology and the Third World World of physical objects or of physical states The world of states of consciousness or of mental states or behavioral dispositions to act The world of objective contents of thought- especially, of scientific and poetic thoughts and of works of art. Popper’s third world resembles Frege’s objective contents of thought. Though it might have similarities, it differs from the following three radically: Plato’s Theory of Forms or Ideas Hegel’s Objective Spirit Bolzano’s theory of universe of propositions-in-themselves and of truths-in-themselves In comparison to ‘belief philosophers’ like Hume, Descartes, Locke, Kant, Berkeley and Russell are concerned with our subjective belief and their source, Popper says that our problem is to find bolder theories where critical preference counts, not belief. Constituents of third world: Theoretical systems Problems Problem situations Critical arguments: most important Content of journals, books and libraries Argument for the independent existence of third world: Two thought experiments: All machines and tools are destroyed- also our subjective learning, including our subjective knwoledge of machines and tools and how to use them. Libraries and our capacity to learn from them survive. The world may get going in this case. Machine and tools are destroyed and our subjective learning, including our subjective knowledge of machines and tools and how to use them. But- all libraries are also destroyed. Here, our capacity to learn from books become useless. Here, the third world is retained in first case and not in the second. This shows the reality, significance and autonomy of third world- also its effect on first and second world. Three Theses of Theory of Scientific Knowledge: 1st thesis- Irrelevance of traditional epistemology Traditional epistemology has studied knowledge or thought only in a subjective sense- with ordinary use of words like- ‘I know.’ Or ‘I am thinking’. This leads only to the study of second world, which is the world of subjects. Popper introduces the existence of two different senses of knowledge or thought: Knowledge or thought in the subjective sense: state of mind or consciousness or disposition to behave or react; Knowledge or thought in an objective sense: theories, arguments and problems. Knowledge in objective sense does not depend on anybody’s belief or disposition to act or to assert. Knowledge in objective sense is knowledge without a knower: it is knowledge without a knowing subject. 2nd thesis- What is Relevant For Epistemology Study of scientific problems and problem situations, of scientific conjectures, of scientific discussions, of critical arguments, of the role played by evidence in arguments and thus, of scientific journals and books, of experiments and their evaluation in scientific arguments- thus, the study of largely autonomous third world of objective knowledge. 3rd thesis- Objectivist epistemology studying the third world can help us to know about the second world of subjective consciousness (especially, subjective thought processes of scientists) but the second world does not play a major role in unraveling the third world Three supporting theses for the above three main ones: Third world is a natural product of the human animal, comparable to a spider’s web. Third world is largely autonomous, even though we constantly act upon it and are acted upon by it. It is our product and has a strong feedback effect on us. Through this interaction between us and the third world, the objective knowledge grows. There is close analogy between growth of knowledge and of biological growth, that is, evolution of plants and animals. A Biological Approach to the Third World Attempt to defend the existence of an autonomous third world using evolutionary or biological argument Biologists study the behavior of animals but also: non-living structures that animals produce like spider’s web, nests of wasps and ants, beaver dams and others. Two categories of problems arising from study of structures- related to: Act of production- methods used by animals, the way animals behave when they are constructing the structures Structure themselves- chemistry of materials used in the structure, geometrical and physical properties, evolutionary changes depending on environmental conditions. Understanding structures from viewpoint of biological functions. There is a feedback relation between these two categories. The problems of the first category are contained within and are suggested by the problems of second category itself. The only presupposition that the first category puts forward is that these structures are produced by some animals. This relationship can be applied to logic and science as well. Three epistemological theses on relation between these two categories: Importance of the distinction between the two categories- We should be aware of the distinction between problems connected with our personal contributions to the production of scientific knowledge on one hand and the problems connected with the structure of various products like scientific theories and arguments on the other. The second category concerned with the products-in-themselves is more important than the first category concerning problems of production- Study of products is more important than the study of production, even for understanding of production and the methods. Problems of second category are basic for understanding the production problems: we can learn about production behavior by studying the products themselves- We can learn about the methodology and heuristics and even the psychology of research by studying the theories and the arguments put forward or against them. This cannot be done through behaviorist, psychological or sociological approach. Objectivity and Autonomy of the Third World The mistaken subjective approach to knowledge arises in believing that a product is nothing without the subject to utilize it. For instance, a book is only a book when it has been really understood- otherwise it is just paper. Reasons against this subjective view: A wasps’ nest is a wasps’ nest even after it has been deserted. A book is a book even if it has never been read. The product might not be produced by a human at all. For instance, a series of books of logarithms produced by a computer. These works together form part of objective knowledge. What can become part of third world? What makes these works objective knowledge is the abstract- the potential of the product to be understood even though this is never actualized. This can be understood through the following scenario: After the human race perished, some books or libraries may be found by some civilized successors and the books may be deciphered. Thus, in order to belong to the third world of objective knowledge, a work should be capable of being grasped by somebody. Metaphysical problem with third world and solution of biological analogue: Some might have a metaphysical issue with existence of the third world. This can be resolved through biological analogue in realm of birds’ nests. I got a bird house for birds- this is a human product, not a bird’s- as a logarithm could be a computer’s product and not human’s. In the world of birds, it is part of the objective problem situation and an objective opportunity. Even though it was never used, it is a bird house. The adequacy of the box is an objective question and its use is partially accidental. This is the case with most ecological niches. They are potentialities and can be studied in an objective way in this manner. Nature of the products of third world: Language is also an unintended by-product of actions which were directed at other aims. The aim and structure of animals and men is not given but develops with the help of feedback mechanism out of earlier aims and out of the results which were or were not aimed at. Language, criticism and the third world The higher functions of human language are the most important of human creations. The two lower functions of language shared by humans and animals are self-expression and signaling. They have two higher functions: descriptive function and argumentative function. The descriptive function leads to emergence of the regulative idea of truth- a description of what fits the facts. The other regulative ideas are content, truth content and verisimilitude. The argumentative function of human language presupposes the descriptive function: arguments are fundamentally about description- they criticize descriptions from point of view of the regulative ideas of truth, content and verisimilitude. Criticism becomes the main instrument for further growth such that logic can be seen as organon of criticism. The autonomous world of higher functions of language is the world of science. We use the schema of error-elimination and of systematic rational criticism for the search of truth and content. The scheme of EE and rational criticism gives a rational description of our self-transcendence by means of selection and rational criticism. Historical remarks: Plato, Hegel and Freud PLATO: AN ESSENTIALIST THIRD-WORLD PLATO POPPER Discovered the third world and also part of the influence or feedback of the third world upon us. Third world divine in nature and unchanging. Third world not divine in nature. It is manmade and changing. Contains only true. Contains both true and false theories, especially open conjectures, problems and refutations. Theory of ultimate explanations: Third world of Forms or Ideas gives ultimate explanations- explanation of essences. Here, the explicans is neither capable or in need of further explanation. We are only concerned with theories, truth- argument. Those who think that concepts and conceptual systems are comparable to theories and theoretical systems, then they are mistaken by Plato’s main error. Concepts are means of formulating theories and while their role is important, they can also be replaced by other concepts. HEGEL: Platonist whose world of Ideas was changing and evolving. Hegel’s Ideas were conscious phenomena: thoughts thinking themselves and inhabiting some kind of mind or Spirit and together with this Spirit, they were changing or evolving. The only similarity between Hegel and Popper: Hegel’s “Objective Spirit” and “Absolute Spirit” are subject to change. HEGEL POPPER Objective spirit consisting of artistic creation and absolute spirit consisting of philosophy contain human production but man is not creative. It is divine self-consciousness of the universe that moves man. This is the theological background on which he works. There is individual creative element, relation of give and take between man and his work. Hegel has a dialectic. Popper’s schema: P1 TT EE P2 Problem 1 Tentative Theory Error Elimination Problem 2 His schema works through error elimination and on scientific level through conscious criticism under the regulative idea of the search for truth. Criticism refers to the process of search for contradictions and in their elimination. Hegel is a relativist. He does not see our task as search for contradictions. He sees contradictory theories as being as good as non-contradictory ones. The aim of science is verisimilitude. Spirit is personalized into a divine consciousness. Ideas inhabit it as human ideas inhabit human consciousness. BOLZANO AND FREGE Popper believes that his theory is closer to Frege’s than to Plato’s or Hegel’s. Logic and Biology of Discovery Epistemology is the theory of growth of knowledge. It is the theory of problem-solving, that is, of constructing, critically discussing, evaluating and critically testing competing conjectural theories. The evaluation or appraisal of competing theories is partly a priori to testing and partly a posteriori to testing. Prior to testing: empirical content of the theory closely related to the virtual explanatory power- its power to solve pre-existing problems- those problems which give rise to the theory and with respect to which these theories are competing. Content and virtual explanatory powers are the most important regulative ideas for the a priori appraisal of theories. They are closely related to their degree of testability. Posterior to testing: truth or verisimilitude is the most important concept in a posteriori appraisal. Verisimilitude is based on the regulative idea of truth content- on the idea of amount of interesting and important true consequences of a theory. Therefore, a tautology has zero truth content and zero verisimilitude. It has probability of one. Content and testability and verisimilitude can be measured by improbability. A posterior evaluation of a theory depends entirely upon the way it stands up to severe tests. These severe tests in turn presuppose a high degree of a priori testability or content. Thus, a posteriori evaluation of theory depends upon it’s a priori value. Theories which are a priori uninteresting need not be tested because their low degree of testability excludes a priori the possibility that they may be subjected to a significant and interesting tests. Biological analogue: animals and plants are problem solvers who tentatively solve their problem through method of competitive tentative solutions and elimination of error. Sense organs also incorporate theory-like expectation such that they are prepared to react to certain selected environmental events- to those events which they expect and only to those events. Those theories which take sense perception as the given or data from which our theory has to be constructed are pre-Darwinian. They do not take into account the fact that the data are adaptive reactions and therefore, interpretations which incorporate theories and prejudices and which are like theories also impregnated with conjectural expectations- there is no pure perception, no pure datum- there can be no pure observational language, since all languages are impregnated with theories and myths. Thus, life in itself proceeds like a scientific discovery from the old problems to new ones. This process of invention and selection contains a rational theory of emergence: P1 TT EE P2 Discovery, Humanism and Self-Transcendence The third world, the world of objective knowledge is man-made. This world exists to a large extent autonomously- it generates its own problems, especially those connected with methods of growth and its impact upon us is greater than the impact any one of us can have on it. We owe our rationality to the third world. Our subjective mind, the practice of critical and self-critical ways of thinking and the corresponding dispositions. The relation between ourselves and our work is also of great importance. Everything depends upon the give and take between ourselves and our work. This interaction between our actions and their results is critical to our life, evolution and mental growth. In this manner, we constantly transcend ourselves, our talents, our gifts. Second world becomes the link between the first and third world- all our actions in the first world are influenced by our second-world grasp of the third world. CHAPTER 4: ON THE THEORY OF THE OBJECTIVE MIND The relation between the three worlds: Second world is the mediator between the first and the third world- the mind can be linked with the objects of both the first world and the third world. The mind establishes an indirect link between the first and third world. The third world influences the first world through its invention of technology. The consequences of these technologies affect the first world. It is possible that originally, the possibilities of technology and its benefits were unknown and thus, were potential and incidental. The second world grasps the third world- in the sense that it grasps the objective thought contents. Language: Human language belongs to all the three worlds. In the first world, it refers to the physical actions and physical symbols. In the second world, it refers to the subjective or psychological state. In the third world, the prime linguistic entities are theories or propositions or statements. Stoics made the distinction between the objective logical content of what we are saying and the objects about which we are speaking. These objects can belong to any of the three worlds. Third-world as a man-made product: There can be broadly two groups of philosophers: Autonomous third world which is considered eternal and divine: Plato Supported by eternal verities: a proposition is true or false timelessly. These were there before man arrived and therefore, aren’t manmade. Language and what it expresses and communicated is manmade- they see everything linguistic as a part of the first and second worlds and they reject that any third world exists: Locke, Mill, Collingwood, Dilthey Agree that there are eternal verities which are not manmade but these eternal verities are not real. Popper introduces a third position: it is possible to accept the reality or the autonomy of the third world and at the same time, admit that the third world originated as a product of human activity. Popper’s position is supported by the effect that the third world has on first world mediated through the second world. Eg: electrical power transmission or atomic theory. The third world is product of men- unplanned product of human actions. We come across problems which are not produced by us but only discovered. In trying to resolve these problems, we invent new theories which are product of our critical and creative thinking. The ontological status of the third world is autonomous in the sense that it is not dependent on its makers. Feedback mechanism: The growth in 3rd world is due to the feedback mechanism between the three worlds such that new problems can always be discovered opening scope for original and creative work. Understanding: Popper’s contribution to the theory of understanding (hermeneutics) It is the understanding of the objects belonging to the third world which constituted the central problem of humanities. Those understandings which belong to objects of second world are dealt with in psychology. Interpretation must be distinguished from the outcome of these activities, interpretation. Interpretation can also be a third-world object, especially a theory. Every interpretation is a kind of theory which is anchored in other theories and in other third-world objects. Three theses concerning subjective act of understanding: Every subjective act of understanding is largely anchored in the third world. Almost all important remarks which can be made about such an act consist in pointing out its relation to the third-world object. Such an act consists in the main of operations with third-world objects: we operate with these objects almost as if they were physical objects. These three theses can be applied to any subjective act of knowledge. All important things we can say about an act of knowledge consists in pointing out the third world objects of the act- the theory or proposition- and its relation to other third-world objects like arguments bearing on the problem and the objects known. CHAPTER 5: THE AIM OF SCIENCE Source: Ratio, Volume 1, Dec 1957 Is there an aim to science? While different scientists have different aims in their endeavors and science itself (if one may take the liberty of using such a phrase) has no inherent aims, it is evident that when we talk about science, we are hinting at that which characterizes scientific activity. Scientific activity is generally considered rational activity and since a rational activity does have some aim, it is possible to say that the attempt to find the aim of science is not completely futile. Aim of science as finding satisfactory explanation: There is a state of affairs in need of an explanation (the explicandum). A set of statements by which one describes the explicandum is called the explicans of the explicandum. The aim of science is to find satisfactory explanation of that which needs to be explained. The explicandum- that which is to be explained- is known to be true or is assumed to be so known. Completely imaginary state of affairs like flying saucers are not considered as eligible for explanation- what is eligible are the reports of flying saucers- however, once it is clear that flying saucers actually exist, there won’t be any need for an explanation of the reports. The explicans will have to be found out. Thus, scientific explanation is the explanation of the known by the unknown. What does it mean for an explanation to be satisfactory? The explicans must entrail the explicandum. The explicans ought to be true. Though it might not be known to be generally true, it must not be known to be false under critical examination. When it is not known to be true, there must be independent evidence in its favor. It must be capable of being tested independently. There are degrees of satisfactoriness. The greater the severity of independent tests it survives, the more satisfactory the explanation will be considered to be. # Explicandum- That which is to be explained + Explicans- The explanation Independent vs ad hoc & circular: Popper understands ‘independent’ in contrast to the opposites ‘ad hoc’ and in severe cases, ‘circular’. Circularity: Cases where the explanation (explicandum) known to be true is in used as an explanation (explicans) of itself. Popper uses the example of roughness of the sea on at a particular time as being caused due to anger of Neptune where the explanation given to support the claim that the sea is rough because Neptune is angry is to circularly justify that the claim stands precisely because the sea is rough whenever Neptune is angry. Ad hoc: An explanation is not ad hoc when the content is rich. Testable consequences- It must have a diverse set of testable consequences. These testable consequences must be different from the explanation itself and are the independent tests and evidence. However, this alone will not ensure satisfactoriness because we could have ad hoc explanations even though it has testable consequences. Universal statements & laws of nature- In using universal statement, we see the explicandum as ‘an instance of reproducible effect’ (193). This is only true if we take into consideration universally testable laws- that is, those laws which are falsifiable. Thus, an explanation is satisfactory depending on its testable and falsifiable universal laws and initial conditions. Reaching highest degree of satisfactory explanation: The greater the explanation ranks in the following characteristics, the more satisfactory it is: testability, content, simplicity, universality and precision. If the aim of science is to find explanation, then it must also find explanation for pre-existent explanations like laws of nature, thus constantly renewing itself. Ultimate explanation: This process of continually renewing and bettering the explanations will resume until we reach an ultimate explanation- that needs no more explanation and is not even capable of being given an explanation. But can there be ultimate explanations? Modified Essentialism: Essentialism says that science must seek ultimate explanations in terms of essences. That is, if I can explain the behavior of a thing in terms of its essence- of its essential properties then no further questions can be raised and none need to be raised. For instance, Descartes believes the essence of physical body to be extension and believed that he had explained physics through this. In the same way, some Newtonians who followed Roger Cotes believes that the essence of matter was its inertia and its power to attract other matter and thus, Newton’s theory could be derived from and ultimately explained by these essential properties of all matter. Criticism: The critics of essentialism have been instrumentalists who have said that scientific theories are nothing but instruments for prediction, without any explanatory power. Modified essentialism: Popper puts forward a third possibility of modified essentialism- Rejection of idea of ultimate explanation- every explanation may be further explained by a theory or a conjecture of a higher degree of universality. There can be no self-explanatory description of an essence. Rejection of all what-is questions: which ask- what is the essence or true nature. We have to give up the idea that there is an essence or an inherent nature or principle in every single thing which is the necessary cause of what it is. Animism: Give up the view that it is the essential properties inherent in each individual or singular thing that can explain the behavior of the object. This does not answer why different things behave in different manners. Explanations must be based on universal laws of nature which would explain the regularities or similarities of individual things or singular facts and events. There laws are not inherent in the things. They are conceived as conjectural descriptions of the structural properties of nature- of our world. However, we cannot describe an ultimate essence of the world through universal laws. Our theories must be universal- it must make assertions about the spatio-temporal regions of the world- that is, about the structural and relational properties of our world. The properties which are described by the explanatory theory must be deeper than those which are to be explained. Here, depth refers to rich content and certain coherence or compactness of the state of affairs described. Problem of depth: Correction of older theories through explanation of new theories marks the depth of a theory (sufficient but not necessary condition) Newton’s theory with Kepler’s and Galileo’s: Newton’s dynamics unified Galileo’s terrestrial and Kepler’s celestial physics Some have said that we can deduce Newton’s theory from the laws of Kepler’s and Galileo’s. However, logically speaking, Newton’s theory contradicts both Galileo’s and Kepler’s. Thus, it is impossible to derive Newton’s theory from Galileo’s or Kepler’s. Why not? Because we cannot proceed from consistent premises to a conclusion which formally contradicts the premises one starts with. This is a very strong argument against induction as well. Contradiction between Newton’s theory with Galileo’s and Kepler’s: GALILEO Galileo: a thrown stone or a projectile moves in a parabola, except in case of free vertical fall when it moves with constant acceleration in a straight line. Newton: Both the above are false for two following reasons- Path of a long-range projectile such as inter-continental missile will not be parabolic but elliptic. It becomes a parabola only if the distance of the flight of the projectile is negligible compared with radius of the earth. For short throws, a parabola is an excellent approximation. We cannot deduce the parabolic track from Newton’s theory unless we add a false initial condition that the radius of the earth is infinite. Galileo: There is constant acceleration. Newton: The acceleration of free-falling bodies is never constant. It increases during the fall because the body is approaching nearer to the center of attraction. We can obtain Galileo’s theory from Newton’s theory if we introduce the false assumption that the radius of earth is infinite. KEPLER Newton: In Newton’s theory, Kepler’s laws are only approximately valid- that is, strictly invalid when we take into account the mutual attraction between the planets. Even Kepler’s third law cannot be more than an approximation except in special cases where the masses of the planets are equal or if unequal, negligible as compared with mass of the sun. This contradicts Newton’s law in the same way Galileo’s does. It is only after we possess Newton’s theory can we find out whether and in what sense, the older theories of Galileo and Kepler are approximations to it. There is no logical step from these theories to Newton’s dynamics. Newton’s theory unified Galileo’s and Kepler’s. Apart from being a mere conjunction of these theories, it corrects them while explaining them. When is a theory deeper than the other one? When it has successfully explained the older theories by correcting them. The demand that a new theory should contain the older ones approximately is the principle of correspondence. This demand is sufficient condition of depth but not a necessary condition. Why not? Because we can see that Maxwell’s electromagnetic wave theory did not correct Fresnel’s wave theory of light. Aim of science To find satisfactory explanations which has following characteristics: Not ad hoc Has independent evidence Stands to severe tests There is no use of metaphysical realism in this task. APPENDIX 1: THE BUCKET AND THE SEARCHLIGHT- TWO THEORIES OF KNOWLEDGE Part 1- Exposition of the ‘bucket theory of science/mind’ Sense experiences are the starting point of any knowledge about the world. This is based on the doctrine that our knowledge/experience consists of: Naïve empiricism: Accumulated perception Bacon and more radically, Kant: Assimilated, sorted and classified perceptions The mind resembles a container- a kind of bucket- where perceptions and knowledge accumulate. True knowledge is pure knowledge, free of prejudices that we are prone to mix with our perceptions. Error results when we make such additions interfering with the process of accumulating knowledge. The perceptions are the raw material which flows from outside of the bucket where it is processed and results in knowledge. Popper- This does not adequately picture the actual process of acquiring experience, especially methods used in research and discovery. Science is impossible without experience but perceptions are not the raw material. The explanations in bucket theory remain only at the level of covering the empirical instances, at some level, becoming circular. Popper agrees with the idea of explanations which transcend the empirical instances which are only the starting point and can be independently tested to come up with hypothesis. Part 2- Role of observation in science In science, observations play a critical role over perceptions. In observation, we play an active part. Definition of observation: Observation is a perception which is planned and prepared. We do not ‘have’ an observation (like ‘have’ a sense experience) but we ‘make’ an observation. An observation is preceded by a particular interest, question or problem- by something theoretical. Every observation is preceded by a problem, a hypothesis (of the form ‘Is this so? Yes or no?’). Since observation is based on our interest it is very selective and presupposes a sort of principle of selection. Part 3- Expectation and process of learning from disappointed expectation All living things react to certain stimuli. These reactions are specific- for each organism the number of possible reactions are limited. That is, at a level, every organism possesses a certain innate set of possible reactions or certain disposition to react in this or that way. This set of dispositions may change with advancing age of the organism or it could remain constant. At any point in the life of the organism, it is invested with a set of possibilities and dispositions to react- this set can be called the (momentary) inner state. An organism ‘learns from experience’ only if its dispositions to react change in the course of time and if such a change is dependent on two factors: change in state of the organism and changing state of the external environment. Thus, in contrast to the bucket theory idea that a change or modification in the dispositions to react is accumulation of memory traces, left over by past perceptions, science holds that the learning process is a certain kind of change that occurs in the organism. Expectation- Expectation is the disposition to react or as a preparation for a reaction, adapted to a state of environment yet to come. We generally become conscious of our expectations only when they are disappointment, due to their being not fulfilled. For instance, if I encounter an unexpected step in my path, it is the unexpectedness of the step which makes me conscious of the fact that I expected to encounter an even surface. Disappointments force us to correct our system of expectations. The process of learning consists in such corrections- that is, in elimination of certain (disappointed) expectations. Part4- Horizon of expectations as frame of reference and birth of explanation An observation is based on a system of expectations. The observation either confirms or refutes the expectation. In every pre-scientific or scientific development, there is a center which Popper calls the ‘horizon of expectations’. This is the sum total of our expectation- subconscious and consciousness. Biological organisms have expectations depending on their level of complexity: animals and babies have horizons of expectations on a lower level of consciousness than a scientist whose expectations are linguistically formulated theories or hypotheses. A horizon of expectation is our frame of reference consisting of varying content at different degrees of consciousness. Explanation: Our observations (presupposing a series of expectations) results in an explanation of the observed phenomena. This explanation transforms our horizon of expectation. Certain parts of it could be destroyed while others will be modified and appropriated into a new horizon of expectations in line with the explanation we arrive at. Process by which explanation comes to be: Confirms expectations Series of Observations Horizon of Expectations about the Observed Phenomena (a tentative hypothesis) Accompanied By Will to Observe (to Come to an Explanation of the Phenomena) Refutes expectations Certain expectations destroyed, others reformed into explanation in line with the observations Expectations integrated into explanation for phenomena The question: ‘What comes first, the hypothesis (H) or the observation (O)?’ is like the question- ‘What comes first, the hen (H) or the egg (O)?’ The bucket theory says that observation precedes hypothesis, like the primitive form of an egg (O) precedes the hen (H). Hypothesis is said to arise from observations by generalization, association or classification. Popper’s Searchlight theory: The hypothesis (expectation or theory) precedes an observation. The hypothesis tells us where to direct our attention and becomes our guide, leading to observational results. Searchlight theory: (in contrast to the bucket theory) Observations are secondary to hypotheses. Observations play important role as tests which a hypothesis must go through. Observation is part of critical examination. If the hypothesis doesn’t pass the examination, then it is falsified and we have to look for new hypothesis. Science: “Straightforward continuation of the pre-scientific repair work on our horizon of expectations” Pg 346. Every move in science presupposes assumptions and a horizon of expectations. The oldest scientific theories are built on pre-scientific myths and still older expectations. Biological analogue: Every biological organism is born with some horizon of expectations. At individual level- ontogenetically (origin and development of individual organism)- the foundational horizon of expectations is that of newborn child. As a species- phylogenetically (relationship between various biological species on tree of evolution)- foundational horizon of expectations is that of unicellular organisms. Role of critical attitude in searchlight theory: Understanding through history of evolution of science Babylonians, Maoris in New Zealand: Cosmological theories- Indoctrination and Blind Following Based on myths; change only little by little based on exposition of inaccuracies when they were handed down, through misunderstanding, through creation of new myths (by prophets or poets). Main aim only to hand down the tradition authentically. Greek: Rise of Critical Attitude The trustworthiness of the myths is questions. The quest for truth begins. Main aim is to criticize theories and role of observation. Diversions occurred in- Anaximander: disciple of Thales Anaximenes: disciple of Anaximander The essence of science is this critical attitude that began in the prescientific myth-making. Part 5- Task of science and elaboration of the theoretical aspect Task of science: The two below are different aspects of one and the same activity. Theoretical: explanation Practical: prediction and technical application Progress of science lies in trials, elimination of errors and more trials guided by experience acquired in course of the previous trials and errors. No theory can be regarded as absolutely certain- every theory can become problematic, regardless of the level of its corroboration. “It is through the falsification of our suppositions that we actually get in touch with ‘reality’.” Pg360 The discovery and elimination of our errors, constitutes ‘positive’ experience we gain from reality. Science is not interested in having last word by adding supplementary hypotheses to save a falsified theory. The point is to learn from our experience, that is, to learn from our mistakes. Formulating theories to show the possibility of their falsification: In form of prohibitions (or negative existential statements) by showing that universal statements are equivalent to negative existential statements. Second law of thermodynamics can be written as: “There does not exist a machine which is 100% efficient” (negative existential statement). Thus, all universal laws can be seen as prohibitions. These prohibitions are only for technicians and not for the scientists. The prohibitions are challenges to testify and falsify. Theoretical aspect: Explanation Logical deduction: a deduction whose conclusion is the explicandum (a statement of the thing to be explained) and whose premises are the explicans (a statement of explaining laws and conditions). Certain demands on character of explicans: that it should be intuitively grasped, should be self-evident have been abandoned in favor of other more necessary demands: that it should be independently testable. Explanation is the deduction of the explicandum from the premises (called explicans). Example: Statement of explicandum: ‘This rat here has died recently.’ Coming up with conjectural or hypothetical explanations which can: (1) Be formulated as explicans from which explicandum can be deduced; (2) Be independently tested. Parts of explicans: Universal laws and initial conditions Universal law- ‘If a rat eats at least 8 grains of rat poison, it will die in 5 minutes’ Initial condition- ‘This rat ate at least 8 grains of rat poison, more than 5 minutes ago.’ Deduction- Therefore, this rat recently has died. Structure of explanation: Part 7 Testing: In case the universal law is questioned, then it can be put through testing to conclude its validity. In the same way, in case the application of the universal law to the individual case is doubted, then the concerning tests can be carried out (like checking content of the rat’s stomach) to check the validity of the conclusion. Explicandum is the effect and the initial conditions are called cause. They both are logically linked through universal law or theory. As the degree of universality of the theory increases, it can be more tested and thus, the range within which it can make predictions also increases and therefore, the chances of falsifications also increases. Part 8- Practical aspect of task of science: predication and technical application Derivation of predictions: The theory is given or assumed to be known and so are the initial conditions. We come to the logical consequences, predictions. Prediction P takes the place of explicandum E in the structure. The predictions can either agree or refute the observations- if it doesn’t agree, then the explicans (the explanation) is falsified. We still do not know if the initial conditions or the universal law is false. Both could be false too. Just because we come up with true predictions does not mean that the explicans is valid. That is, true predictions don’t verify the explanation. The explanation has to pass through severe tests before it can be declared valis. Technical application: If the task is to build a bridge, we are given the specifications (S) which are the customer’s requirements distinct from architect’s specifications. We are also given relevant physical theories- universal laws. Here, we replace the explicandum E with the S, the specifications to be met. Part 10- Example- Transition from Kepler and Galileo to Newton’s theory Newton’s theory is not a generalization from Galileo’s and Kepler’s. They contradict his theory. Kepler and Newton Kepler’s laws cannot be deduced from Newton’s. Kepler’s laws can only be obtained approximately from Newton’s. Galileo and Newton Galileo’s law of free falling bodies cannot be deduced from Netwon’s theory. It contradicts his theory. Concluding remarks Newton’s theory cannot be a generalization obtained by induction or deduction. It is a new hypothesis which can make way for falsification of the old theories- by showing the domains within which Newton can yield better approximations than Galileo and Kepler. Kepler: Domain of theory of perturbations Galileo: Theory of variable accelerations If Newton’s theory had only been a generalization from Kepler’s and Galileo’s, then it would have been a circular explanation of these laws and thus an unsatisfactory explanation. His theory opened independent tests which led to successful prediction making it better than the older theories. Newton’s theory is an example of an attempt to explain certain older theories of lower degree of universality- it leads not only to a sort of unification but to their falsifications. The older theory thus has been partly successful (made way for the new theory) and also failed. PART 11- Shift from mechanical models to abstract theory From Descartes to Maxwell, all the newly discovered relations were explained in terms of mechanical models through laws of push or pressure. This became the model for understanding in science. This was first defeated by Newton. That the theory be independently testable was the only prime demand made on a theory. We could work with theories which were not strictly mechanical- they could be presented diagrammatically or through ‘abstract’ mathematical theories. AIM OF SCIENCE: “..It is the invention of ever new theories and the indefatigable examination of their power to throw light on experience…the aim of science is not to discover absolute certainty, but to discover better and better theories (or to invent more and more powerful searchlights) capable of being put to more and more severe tests. But this means that these theories must be falsifiable: it is through their falsification that science progresses.” Philosophy of Science Study Resource-2 22-April-2015