Vartanian 1 Gary Vartanian Phil 8 Midterm Study Guide 1) Logical positivism What are its primary doctrines? Analytic/Synthetic Distinction and Verification Theory of Meaning o Logical positivism is a way of thinking popular in the mid-20th century which attempted to make philosophy more rigorous by creating criteria for evaluating the truth or falsity of certain philosophical statements. Its main criteria for any statement is verifiability, which comes from two different sources: empirical statements, which come from science, and analytic truth, statements which are true or false by definition. Logical positivism is an absolutist way of looking at statements and labeling them either true, false, or meaningless. A key component of logical positivism is that it rejected statements about ethics and aesthetics as being unverifiable, and therefore not a part of serious philosophical thinking. To have meaning, a given statement had to be connected to either empirical data or analytic truth. 2) Analytic versus synthetic statements: What is it for a statement to be analytic? Analytic statements are true or false just in virtue of their meaning alone. Ex) ‘Triangles have three sides’, ‘Bachelors are unmarried’, ‘Bachelors are married’, ‘Murder is wrong What is it for a statement to be synthetic? o A synthetic claim is one that is not analytic. The truth of a synthetic claim does depend upon how the world is. So, these claims are substantively about the world. Ex) The President of the United States is Barack Obama’, ‘The Los Angeles Dodgers came from Brooklyn’, ‘Physics is a difficult subject. Elaboration: Some sentences are true or false simply in virtue of their meaning, regardless of how the world happens to be; these are Analytic. Ex) “All bachelors are unmarried” Analytic Analytic truths are, in a sense, empty truths, with no factual content. Logical positivists claimed that all of mathematics and logic is analytic. For logical positivism, mathematical propositions do not describe the world; they merely record our conventional decision to use symbols in a particular way. But proofs and investigation within mathematics itself are analytic. A Synthetic sentence is true or false in virtue of both the meaning of the sentence and how the world actually is. “All bachelors are bald” Synthetic Synthetic claims about the world can be expressed using mathematical language, such as when it is claimed that there are nine planets in the solar system. Earlier philosophers in the rationalist tradition had claimed that some things can be known a priori; this means known independently of experience. Logical positivism held that the only things that seem to be knowable a priori are analytic and hence empty of factual content. 3) A priori versus a posteriori: Vartanian 2 a) What is it for a statement to be a priori? A priori knowledge or justification is independent of experience. o A priori with analytic. o Facts. b) What is it for a statement to be a posteriori? A posteriori (Empirical evidence) is a source of knowledge acquired by means of observation or experimentation. o A posteriori with synthetic. o Observations. Elaboration: Logical positivism held that the only things that seem to be knowable a priori are analytic and hence empty of factual content. We can combine this distinction with the a priori / a posteriori distinction. It looks like analytic claims are also a priori. I do not need to make observations to know that all bachelors are unmarried. There do not seem to be statements that are analytic and a posteriori. There are clearly synthetic, a posteriori claims. (For example, ‘Physics is a difficult subject.’) In general, people who think that there are no synthetic a priori claims are empiricists: Any substantive claim about the world can only be known to be true by observation; hence, the emphasis is on the empirical. Mathematics and logic are analytic on this way of thinking of things, so they are known a priori. Physical science is all a posteriori since synthetic. Galen Strawson wrote that an a priori argument is one in which "you can see that it is true just lying on your couch. You don't have to get up off your couch and go outside and examine the way things are in the physical world. You don't have to do any science." a posteriori knowledge or justification is dependent on experience or empirical evidence (for example "Some bachelors are very happy"). A posteriori justification makes reference to experience; but the issue concerns how one knows the proposition or claim in question, or better say, what evidences one has to verify the validity of proposition. 4) The analytic/synthetic distinction and the a priori / a posteriori knowledge? a) How do analytic claims allow for non-mysterious a priori knowledge? Analytic statements are true or false just in virtue of their meaning alone. Ex) Bachelors are unmarried OBVIOUSLY TRUE, by meaning alone. Analytic statements are a priori. I do not need to make observations to know that all bachelors are unmarried. There do not seem to be statements that are analytic and a posteriori. Synthetic claims is one that is not analytic. Ex) The President of the United States is Barrack Obama. The truth of a synthetic claim does depend upon how the world is. There are synthetic, a posteriori claims. Ex) Physics is a difficult subject. People who think that there are no synthetic a priori claims are empiricists. Empiricists claim that any substantive claim about the world can only be known to be true by observation; hence the emphasis on the empirical. People who think that there are synthetic a priori claims are rationalists, for they think that reason can discover substantive truths. b) What is the problem with synthetic, a priori knowledge? Vartanian 3 a priori proposition: a proposition whose justification does not rely upon experience. Moreover, the proposition can be validated by experience, but is not grounded in experience. Therefore, it is logically necessary. a posteriori proposition: a proposition whose justification does rely upon experience. The proposition is validated by, and grounded in, experience. Therefore, it is logically contingent. Examples of a priori propositions include: "All bachelors are unmarried." "7 + 5 = 12." Examples of a posteriori propositions, on the other hand, include: "All bachelors are unhappy." "Tables exist." Both of these propositions are a posteriori: Any justification of them would require one to rely upon one's experience. 5) Verification Theory of Meaning a) What is it? A (non-analytic) statement is only meaningful if it is verifiable1 by sense experience. So, any meaningful sentence must have consequences that can be tested by observation. If it does not have such consequences, it is not meaningful. The verification theory (of meaning) is a philosophical theory proposed by the logical positivists of the Vienna Circle. A simplified form of the theory states that a proposition's meaning is determined by the method through which it is empirically verified. In other words, if something cannot be empirically verified, it is meaningless. For example, the statement "It is raining" is meaningless unless there is a way whereby one could, in principle, verify whether or not it is in fact raining. The theory has radical consequences for traditional philosophy as it, if correct, would render much of past philosophical work meaningless, for example metaphysics and ethics. The theory is meant to be applied only to synthetic claims (i.e. claims about the world), rather than analytical ones. The statement of the theory itself was taken by Ayer to be an analytic claim. Verifiability theory of meaning: o Here is how the theory was often put: the meaning of a sentence consists in its method of verification. (knowing the meaning of a sentence is knowing how to verify it). Key application of the principle: If a sentence has no possible method of verification, it has no meaning. By “verification” here, the positivists meant verification by means of observation. Observation in all these discussion is construed broadly, to include all kinds of sensory experience. A better word would be “testability.” This is because testing is an attempt to work out whether something is true or false, and that is what the positivists had in mind. o Verification is a strong empiricist principle; experience is the only source of meaning, as well as the only source of knowledge. b) What would be an example of a sentence that is meaningless according to its proponents? Why would it be considered meaningless? Scrodinger’s cat? I am fat. c) What attractions does the view have? Vartanian 4 What is thought to be attractive about this view of meaning? 1) Many empiricists have thought that a person who has been blind from birth could not know what ‘red’ means. So, they would not understand (at least) one of the words in a sentence like ‘The table in my kitchen is red.’ We learn the meanings of some words via direct sensory impressions. So, it seems like our ability to understand major portions of language involve having had appropriate sense experiences and that the meanings of major portions of language have to do with those sense experiences. 2) This explains, perhaps, why philosophy is so hard to understand. When one reads various philosophers (for example, Heidegger), one finds claims like ‘The nothing nothings’ that one does not understand. What would help one to understand it? Intuitively, if Heidegger could tell us what observational difference it makes whether the nothing nothings or whether it does not, then we would know something about what claim is being made about the world. 3) Unlike much of philosophy, science seems to only make statements that are tied very closely to sense experience. For example, Einstein showed how claims about simultaneity could be verified by sense experience. This might be why physics is much clearer than philosophy. It is clear what the claims of physics mean because they are linked to sense experience (experimental evidence). And, that link to sense experience is required for a statement to have meaning. So the positivists thought, for example, that a claim like “This particle is in absolute rest” does not mean anything because no experiment could determine it to be true or false. 4) As an added bonus, we are able to dissolve various philosophical problems which otherwise defy solution. For example, the traditional “Problem of the External World” becomes impossible to state in such a way that it is problematic. One wants to know whether it is true that there is a real world that corresponds with our sensations or whether our sensations are all just illusory and the real world does not really exist. If this “real world” is something unobservable because all that we ever observe are our own mental impressions, then this question has no meaning because we can never make an observation that would tell us whether this real world is there.2 So, there is nothing to worry about here. If claims about the “real world” are just claims about the stability of our sensations, then we can just directly observe that the real world exists. For example, the claim “There is a real tree in the courtyard which is not just a hallucination” just means that my mental impressions have a certain stability that hallucinations lack. But, if this is all that it means, then I can check it by observation. So, there is no philosophical problem here either way. d) What problems does it face? What is unattractive about the view? 1) ‘Verifiable’ is imprecise, and the imprecision is (at least) two-fold: a. It is not clear what the ‘able’ means. It might mean that we need to be able to verify the statement in practice. That is, it must now be within our ability to verify it. But, if it meant that, then a sentence like ‘The average atmospheric temperature on the nearest extra-solar system planet is 150 degrees’ would not be meaningful. (Let us assume that we do not currently have the means --- the technology --- to verify it. Perhaps we actually do.) But, that does not seem plausible since I sure think I know what the sentence means. So, the ‘able’ needs to mean that we are in principle able to verify it. But, unfortunately it is a bit unclear what this means. Can we even in principle verify (or falsify) the claim ‘There was a fly on Caesar’s nose when he crossed the Rubicon’? It is not just a technological limitation on us that we cannot go back in time and check.3 But, in some sense, we know what observations would count as verifying it even if we cannot put ourselves in the position to make those observations. Perhaps that is all that it would take to be able to verify it in principle. b. It is not clear what the ‘Verify’ means. It could mean: i. To come to know with certainty that a claim is true. But, in that case, it might be argued that the only thing I know with certainty is the content of my own sensations (or sense impressions or sense-data). Even claims like ‘I see a tree in front of me’ are not things about which I can be certain because I only actually see a tree in front of me if there is, in fact, a tree in front of me.4 And, I could be wrong about that since it might be a fake tree. So, the only things I can verify --in this strong sense --- are claims about my own private sense impressions. Other claims about material objects, say, must just mean something having to do with my sense impressions. So, claims like “There is a tree in front of me” --- if it is to Vartanian 5 be taken to be meaningful as it ought to be --- must mean something like “I am having a stable impression of a green-ish, leafy-like thing with a long brownish stem.” (The view that claims about physical objects just mean claims about sensory impressions is known as “phenomenalism.”) One problem with this view is that the only things that are verifiable have to do with my sense impressions and these seem to be too private for the business of science. ii. To come to have some evidence in favor of. If this is what ‘verify’ means, then I can verify “There is a tree in front of me” even if that claim doesn’t just mean something having to do with sensation. For, having an impression of a tree is some evidence --- even if not conclusive evidence --- that there is a tree in front of me. But, we need to hear more to know what it is to have acquired some evidence for a claim. 2) The verificationist theory of meaning seems to be self-refuting in that it is not easy to see how one could verify by sense experience that it is the correct view of meaning. e) Is there any vagueness in what the view really amounts to? If so what is it? See above, am not typing again. Dr.Who?? f) What is “in practice verifiability” versus “in principle verifiability” What motivates drawing this distinction? o Difference between “observational” language and “theoretical” language.” “Red” is in the observational part of language, and “electron” is in the theoretical part. An important question was where to draw the line. Schlick stayed closed to traditional empiricism. Neurath, argued that terms referring to many ordinary physical objects are in the observational part of language. Only the observation statements about physical objects can be the basis of public or ”intersubjective” testing. 6) Quine’s Challenge to Logical Positivism a) What is holism about confirmation? A holist argues that you cannot understand a particular thing without looking at its place in a larger whole. Holism about testing says that we can only test complex networks of claims and assumptions. This is because only a complex network of claims and assumptions make definite predictions about what we should observe. Quine's extension of underdetermination to all knowledge claims, since no theory of any type can be tested in isolation, but only embedded on a background of innumerable and often undetermined factors. (See Quine-Duhem thesis.) Confirmation holism thus involves the problem of credit assignment, determining which aspect of the overall network to attribute a theory's failure to. And by ontological relativity, explicated by Quine, one can always protect one's explanation of phenomena by attributing failure to some aspect outside the explanation. Elaboration: W.V. Quine’s criticism in “Two Dogmas of Empiricism” o Quine argued for a holistic theory of testing. o A holist argues that you cannot understand a particular thing without looking at its place in a larger whole. Holism about testing says that we can only test complex networks of claims and assumptions. This is because only a complex network of claims and assumptions make definite predictions about what we should observe. o So whenever you think of yourself as testing a single idea, what you are really testing is a long, complicated conjunction of statements; it is the whole conjunction that gives you a definite prediction. If a test has an unexpected result, then something in that conjunction is false, but the failure of the test itself does not tell you where the error is. The unexpected observations within your experiments are telling you that something is wrong, but the problem might lie with one of your background assumptions, not with the hypothesis you were trying to test. Vartanian 6 o o o Although the logical positivists officially accepted a holistic view about testing, they did not appreciate the significance of the point. The verifiability principle seems to suggest that you can test sentences one at a time. Strictly, the positivists generally held that these observations are only associated with a specific hypothesis against a background of other assumptions. Quine said that the idea of analyticity was intended to treat some claims as immune to revision, and he argued that in fact no statement is immune to revision. Quine argued that there is no way to make scientific sense of a sharp analyticsynthetic distinction. b) How is holism about confirmation a threat to the verification theory of meaning? From book: “The Verifiability principle seems to suggest you can test sentences one at a time.” From notes: “The Verificationist theory of meaning assumes that (synthetic sentences are individually testable… But Quince pointed out, we test only groups of sentences. (Holistic theory of testing). A single sentence does not generally have observational consequences.” From notes: “The Verificationist theory seemed to depend upon the idea that sentences can be tested individually in the sense that each sentence has observable consequences of its own. BUT, THIS ISN’T TRUE (claim known as Quine-Duhem thesis). Quine: Our claims “face the tribunal of experience… as a corporate body.”” c) Why do considerations in the vicinity bring into doubt the relevance of the analytic/synthetic distinction? From notes: “Say that our set of sentences made a false prediction. Then, logic does not tell where the problem was (which sentence was false)… Claim eyesight is bad, therefore know that there is tree in front of me, but can’t prove because vision is bad. (Can’t prove wrong).” “ All claims can be held immune to revision from sense experience. BUT, LIKEWISE, I can – Quine thinks – place the blame for the false prediction anywhere… Thus, no claims are such that they cannot be given up on the basis of sense experience. SO in that sense, all claims appear to have the hallmark of the synthetic. From book: “Quine argued that analytic-synthetic distinction does not exist;” “Quine said that the idea of analyticity was intened to treat some claims as immune to revision, and he argued that in fact no statement is immune to revision.” “Quine argued that there is no way to make scientific sense of a sharp analytic-snythetic distinction. He connected this point to his holism about testing. For Quine, all our ideas and hypotheses form a single “web of belief”, which has contact with experience only as a whole. An unexpected observation can prompt us to make a great variety of possible changes to the web. Even sentences that might look analytic can be revised in response to experience in some circumstance.” 7) Induction versus Deduction a) What is the difference between induction and deduction? Induction Generalize Deduction Specify. From notes: “We might get an incorrect conclusion since a deductive argument can be valid – if the premises are all true, then the conclusion has to be true as well – even thought he conclusion is not, in fact, true.” “The steps that gets you from the premises to the conclusion would not be at fault since it transmits truth. So, our only real worry with valid deductive arguments is whether our premises are true. From book: “Deductive logic is the well-understood and less controversial kind of logic. It is a theory of patters of argument that transmit truth with certainty. These arguments have the feature that if the premises of the argument are true, the conclusion is guaranteed to be true. An argument of this kind is deductively valid. Ex) Premises: All men are mortal Socrates is a man Conclusion: Socrates is a mortal. Vartanian 7 A deductively valid argument might have false premises. In that case the conclusion might be false as well. BUT, the logical empiricists thought that the great aim of science is to discover and establish generalization (describing “laws of nature”) The key idea was that science aims at formulating and testing generalization, and these generalization were seen as having an infinite range of applications. Induction inferences from particular observations in support of generalizations. Ex) “All the many swans observed so far have been white.” This conclusion will be the claim that all swans are white – a conclusion that cold well be false but which is supported, to some extent by the evidence. A form of inference closely related to induction is projection. In a projection, we infer from a number of observed cases to arrive at a prediction about the next case, not to generalization about all cases. 7b) Be prepared to give an example of a deductive argument and an inductive argument. Deductive reasoning happens when a researcher works from the more general information to the more specific. Sometimes this is called the “top-down” approach because the researcher starts at the top with a very broad spectrum of information and they work their way down to a specific conclusion. Deductive: All men are mortal Socrates is a man Conclusion: Socrates is a mortal. Premises: Inductive: All swans encountered so far at the lake are white. All the swans at the lake are white. 7c) What are some of the types of inductive argument? In particular, what is an “enumerative induction” and what is an “abductive inference”? From notes: “Enumerative induction:” The premises are just an enumeration of various entities all of which have certain combination of properties (e.x. an enumeration of a bunch of swan that are white). And the conclusion claims that everything that has the first property also has the second. Ex) Enumerative induction or, as the basic form of inductive inference, simply induction, is an inference from particular instances to all instances, thus an unrestricted generalization or universal generalization. For instance, if one observes 100 swans, and all 100 were white, one might infer All swans are white. As the truth of this reasoning form's premises—100 observed swans and 100 white swans—does not entail the truth of its conclusion, this is an inductive inference, which is logically invalid. “Abductive Inference:” (or inference to the best explanation) we infer that the best explanation of a certain phenomenon is true. Our evidence that there was a larger meteor that hit the Earth 65 million years ago is Vartanian 8 the presence of rare elements in layers of the Earth’s crust that are that old. And, the reason we think the presence of those elements is evidence that a meteor hit is that --- as far as we know --- that is the best explanation of the presence of those elements. Ex) For example, the lawn is wet. But if it rained last night, then it would be unsurprising that the lawn is wet. Therefore, by abductive reasoning, the possibility that it rained last night is reasonable. Peirce argues that good abductive reasoning from P to Q involves not simply a determination that, e.g., Q is sufficient for P, but also that Q is among the most economical explanations for P. 7d) What is the “problem of induction”? How induction works? And what justifies it – Nelson goodman’s grue problem. 8) Hypothetico-Deductivism 8a) How does one confirm a hypothesis according to the H-D view? From Notes: We confirm a generalization when one of its consequences turns out to be true. After many repeated correct prediction, it will confirm it more and more. 8b) What reasons are there for thinking that the H-D view cannot correctly represent what it takes to confirm a hypothesis. See GRUE problem and Curve fitting problem 9) Nelson Goodman’s “Grue” Problem 9a) How is grue defined? An object is grue if and only if it was first observed before 2020 and is green, or if it was not first observed before 2020 and is blue. 9b) How does Goodman’s definition of ‘grue’ generate a problem for the justification of induction? What challenge does it raise? Goodman point is that 2 inductive arguments have the exact same form, but one argument can be good while the other is bad. SO what makes an inductive argument good or bad one cannot be just its form. Consequently, there can be no purely formal theory of induction and confirmation. SO Goodman claimed that whether or not a term ‘contains a reference to time’ or ‘is defined in terms of time’ is a language relative matter. Terms that look OK from the standpoint of one language will odd from another. 10) Karl Popper a) How does his project differ from the point of the logical positivists? From notes: 1) Popper is not trying to give an account of what sentences count as meaningful. Rather, he is trying to delineate the difference between genuine science and pseudo- science (i.e. he wants to solve The Demarcation Problem). Pseudo-scientific claims are meaningful (and, thus, possibly even true), they just aren’t science. Popper would like to see what the difference between pseudo-science and science is. 2) Popper believes that induction is irrational since unjustified. The problem of induction has not been solved because it cannot be.2 No matter how many instances of green emeralds one sees, that does not justify believing that all emeralds are green. So, the sentence ‘All emeralds are green’ is not verifiable by induction even in the weak sense that we have good --- though not conclusive --- evidence for it. However, a single non-green emerald shows deductively that the sentence ‘All emeralds are green’ is false. So, it is falsification (rather than verification) that is important in science since it does not require irrational induction but only requires deduction. Sumation: A hypothesis is scientific if and only if it has the possibility of being refuted (falsified) by some possible observation. 10b) What is the Demarcation Problem? Popper called the problem of distinguishing science from pseudoscience the Demarcation Problem. Vartanian 9 It is Falsification rather than verification that is important in science since it does not require irrational induction but only requires deduction. Falsification claims that a hypothesis is scientific if and only if it has the potential to be reftured by some possible observation. To be scientific, a hypothesis has to take a risk. He claimed that all testing in science has the form of attempting to refute theories by means of observation. Confirmation is myth. The only thing an observational test can do is show that a theory is false. Popper placed great emphasis on the idea that we can never be completely sure that a theory is true. However, almost all phiosophers of science accept that we can never be 100 percent certain about factual matters. This position, that we can never be completely certain about factual issues, is often known as fallibilism. We then check to see if the prediction comes out as the theory says it will. If the prediction fails, then we have refuted, or falsified the theory. If the prediction does come out as predicted, then all we should say is that we have not yet falsified the theory. 10) c) What is Popper’s view of induction? d) How does Popper think that the scientific method works if it does not use induction? e) What is a bold conjecture according to Popper? Notes: The method of science according to Popper is one of conjecture and refutation: 1) Scientists like Newton do not use induction to arrive at hypotheses. Rather, they make bold conjectures. One formulates a hypothesis that “takes a risk” in the sense that it makes predictions such that if they are false the theory is refuted. The more risks that a scientific theory takes the better. At the limit where a theory takes no risk of being refuted at all, it is not scientific. 2) The second stage is one of attempted refutations. Scientists attempt to refute their own theories by experiments. If the theory is refuted by the experiment, then they have to make a new bold conjecture.4 If the theory is not refuted by the experiment that does not justify us in believing that the theory is true or even probably true. (That would be to use induction.) The most we can say is that it has not yet been refuted. Book: Popper also used the idea of falsification to propose a theory of scientific change. Stage 1 in the cycle is conjecture—a scientist will offer a hypothesis that might describe and explain some part of the world. A good conjecture is a boldone, one that takes a lot of risks by making novel predictions. Stage 2 in the cycle is attempted refutation—the hypothesis is subjected to critical testing, in an attempt to show that it is false. Once the hypothesis is refuted, we go back to stage 1 again—a new conjecture is offered. That is followed by stage 2, and so on. Instead, a scientist should constantly strive to increase the breadth of application of a theory and increase the precision of its predictions. That means constantly trying to increase the “boldness” of conjectures. Vartanian 10 Very important distinction: between descriptive and normative theories. o A descriptive theory is an attempt to describe what actually goes on, or what something is like, without making value judgments. o A normative theory does make value judgment; it talks about what should go on, or what things should be like. There are three answers to our question about how science works: o Empiricism: The only source of real knowledge about the world is experience. Empiricism and Science: Scientific thinking and investigation have the same basic pattern as everyday thinking and investigation. In each case, the only source of real knowledge about the world is EXPERIENCE. But science is especially successful because it is organized, systematic, and especially responsive to experience. Ex1) Ognaz Semmelweiss: Showed that by washing hands before delivery, baby has higher chance for living. Ex2) John Snow: maped out sewers and showed correlation between cholera outbreak and infection in water supply. o Language of Mathematics: Mathematics and Science: What makes science different from other kinds of investigation, and especially successful, is its attempt to understand the natural world using mathematical tools. We might argue that mathematics, used as a tool within an empiricist outlook is what makes science special. Reason, why math is badass: o Used in physics, chem, … Reason, why math is not badass: o No math in biology. Ex) Darwin Origin of Species o Scientific Communities: Social Structure and Science: What makes science different from other kinds of investigation, and especially successful, is its unique social structure. Vartanian 11 SO TRUST AND COOPERATION ARE ESSENTIAL TO SCIENCE! (GAME THEORY) Shapin argues that when we look closely, a great deal of what went on in the Scientific Revolution had to do with working out new ways of policing, controlling, and coordinating the actions of groups of people in the activity of research. These accounts of science stress the special balance of cooperation and competition found in the scientific communities. A key part of the scientific societies role was to handle the allocation of credit in an efficient way – making sure the right people were rewarded, without hindering the free spread of ideas. These societies also functioned to create a community of people who could trust each other as reliable co-workers and sources of data. The empiricist can argue that this social organization made scientific communities uniquely responsive to experience.