- Oldroyd points out that Popper claims to be a realist, as opposed to instrumentalism: but Oldroyd (and Ess) go on to argue that Popper's position ends up supporting instrumentalism rather than realism.
- Popper developed a theory of falsification (Oldroyd, 300)
- Popper came to 7 conclusions (Oldroyd, 300)
Ess Lecture Notes
- Beginning with Comte, as we saw, and continuing through the 19th and early 20th centuries, there was the positivist/realist movement. By the early 1900's, a principle school of positivism/realism was developed by a group of people later known as the "Vienna Circle." For them natural science is the only legitimate mode of knowledge.
They tended to hold that the Verifiability Criterion works to distinguish the legitimate knowledge of the natural sciences from claims to knowledge found in philosophy and religion.
The verifiability criterion can be paraphrased this way:
(1) A term has meaning if and only if that meaning is fully grounded in observation of the external world via the senses and/or their instruments.
(2) Once it has meaning it can then be decided whether it is true or false.
Applying this criterion to knowledge-claims in the natural sciences, philosophy, and religion, was supposed to lead to the following split:
However, it soon became apparent that the Verifiability Criterion was not self-referential. That is, if we try to apply the the V.C. to itself, we have to ask "What sense experience can we point to that gives meaning - and thus the possibility of verification - to the claim that 'A statement is meaningful only if it can be verified in sense experience?'" Truth claims such as "Material bodies have weight," can have meaning and be verfied in sense experience because we have sense experience of material bodies and of weight. Unlike such claims - what is the sense experience we must point to in order to establish meaning and verification for "meaningful" as used in the Verifiability Criterion?
The simple answer is: there is none. But this means that by applying the Verifiability Criterion to itself, we are forced to admit that the V.C. itself is not meaningful or verifiable. So why accept it?
[It turns out that something called Goedel's proof (1931) demonstrated
that no axiomatic system can be both consistent and complete.
This means that perhaps the problem with the verifiability
criterion can be solved by attempting to defend it not
with itself (i.e., within a system consisting of the V.C.
and the knowledge claims of the natural sciences which it justifies:
such an approach presumes that the system must be both complete
and consistent). Rather, perhaps we can give meaning to the V.C.
by appealing to a "background" language and set of assumptions
(i.e., outside the system.) The positivists don't like
this approach, however, because it suggests that the natural sciences
are more anchored in the culturally relative seedbed of non-scientific
language, thoughts, etc., than they would like to claim. The upshot
is that the positivists seem caught between insisting on the V.C.
- but for no defensible reason - or admitting that the
V.C. requires a background language, etc., which opens the door
to relativism, etc. In light of this dilemma, many folk - especially
following Popper's "last-ditch" effort to "save"
empiricism/positivism/realism with the falsifiability criterion
- have agreed that positivism is a dead-end.]
[In addition] In 1905 Einstein shocked the world with his theory of special relativity, and then later with his theory of general relativity. These relativity theories, along with quantum mechanics, result in a general shifting from the realist view to a instrumentalist view.
- Popper responded as a sort of "modified realist". He realized the problem of the "third cause" when trying to confirm any instance.
This problem can also be stated as the problem of affirming the
consequent in attempting to find confirming experimental evidence
for one's hypotheses. [That is, in attempting todiscover confirming
evidence, we reason as follows:
H (hypothesis) ---> E (experimental evidence)
(implies)
E (the predicted consequences, the experimental evidence, is found)
Therefore: H (we affirm that our hypothesis is true)
BUT, this same argument form leads us to obviously false conclusions - e.g.:
I (if I have strawberries in my pocket) ---> R (then there's red fruit
in my pocket)
R (examination shows I have red fruit in my pocket)
Therefore: I (there must be strawberries in my pocket)
The problem, of course, is that the red fruit could be an apple, tomatoe, cranberries, etc. Likewise, the evidence E may be the result of some other cause besides the one suggested by our hypothesis. For example:
H = Breathing causes drug addiction
If this hypothesis were true, then I should expect to find that all drug addicts started in life as breathers. So my experiment - E - the evidence that, if true, would allegedly confirm my hypothesis, would be to examine all drug addicts to determine how many of them started in life as breathers. Again, the form of the argument so far is:
H ---> E
Let's say that I discover, out of a sample of 100 drug addicts, that sure enough, all 100 started in life as breathers. That is, E, my confirming experiment, turns out to be true. According to the form of the argument, I would then conclude that my original hypothesis H is true. That is, in symbolic notation, my argument would be:
H ---> E
E (i.e., all drug addicts examined started in life as breathers)
Therefore: H
So, while it's certainly true that all drug addicts used oxygen
before they became drug addicts, - we don't believe that drug
addiction is caused by breathing oxygen. Yet, using the same form
of argument used originally in determining confirming experimental
evidence for hypotheses, we could just as easily conclude that
the evidence demonstrates that in fact our original hypothesis
(oxygen causes drug addiction) is true. The point is that the
argument form we are using here is clearly fallacious -
i.e., it can begin with truepremises and land us in false conclusions.]
In part because he recognized this problem - called the fallacy of affirming the consequent - Popper developed the falsifiability criterion for hypotheses. Logically one cannot find decisively confirming instances. However, one can find non-confirming instances. Science is then a matter of developing hyptheses - and then attempting to falsify hypotheses. Those that withstand this negative criticism, we presume, are closer to Truth than those which can be falsified.
Notice that Popper's project is thus a modification of the original program of the positivists. First of all, as he puts it, he is simply attempting to demarcate - to distinguish between - natural science, on the one hand, and philosophy, religion, etc., on the other.
This means, moreover, giving up the original positivist claims that science always gives you truth. Rather, the falsifiability criterion can only demonstrate that the hypotheses which survive the attempt to falsify them are less false than those which can be falsified. [In technical terms, science is now understood to be on an "assymptotic approach" to Truth - an approach that brings one closer to Truth, perhaps, but which never ultimately arrives.]
Thirdly, because Popper is no longer claiming that the natural sciences "give us truth" - nor can he claim (as did the earlier positivists by way of the Verifiability Criterion) that only the sciences can give us truth or have meaningingful claims to knowledge. Rather, he says explicitly that his only interest is to provide a criterion for distinguishing between the two sorts of claims (natural sciences on the one hand, which he holds to be falsifiable - but not necessarily true -, and philosophy, religion, etc., on the other hand): he is not making claims about the truth or meaning of claims in either science or philosophy, religion, etc.
To say it still another way, Popper moves from the much stronger claims of the positivists (that the natural sciences, and only the natural sciences, contain truth - as guaranteed by the Verifiability Criterion) to the much more modest claim that we can only distinguish between the claims of science and other claims because the former are falsifiable.
To say it a last way, Popper represents a shift from the positivists claim that the natural sciences are the exclusive domain of truth (philosophy and religion are by definition non-sense and false) to the admission of pluralism, to the possibility that claims in different areas (science, philosophy, religion and so on) can all be true.
But all this means, finally, that we also shift from truth as defined within the realist/positivist camp [Truth = correspondence between theory//reality]. Such a notion of truth makes no sense if one admits, as Popper does, that even the natural sciences do not give us "Truth," but are always only moving away from more false to less false hypotheses. That is, the assymptotic approach means that my current hypothesis may be replaced tomorrow by one that is less false. And that one, in turn, may be replaced the day by one even less false, etc. But this means, simply, that at no time am I in possession of "Truth," - only of approximations to Truth. But this means, finally, that if I have no access to "Truth" - then I cannot determine whether my current hypothesis accurately "corresponds" to Reality.
In this way, despite his claims to being a realist, Popper's falsifiability criterion in fact forces us into an instrumentalist posture. The best I can claim for my hypotheses, as successively less false, is only that they are approximations of Reality, and in this sense, they are only approximate models or theoretical instruments for knowing the world about me. Truth on this view becomes "what works," - i.e., it allows us to more or less accurately predict and control phenomena.
For example, Newtonian mechanics - with deterministic, causal notions of "gravity," motion continuing in a straight line unless disturbed by other forces, etc. - is a pretty good model: it allows us to send men to the moon and planetary probes to Jupiter. But it is not "Truth" - at least as Reality is currently understood from the standpoint of relativity theories and quantum mechanics. Rather, ultimate Reality on these views is probabilistic - and "gravity," in particular, is not a separate "force" of attraction,
...but the intrinsic structure of spacetime! Spacetime is like a nonrigid expanse of rubber deformed by the presence of stars and planets and their accompanying gravitational fields. The planets do not orbit the sun because of some force, some action at a distance acting instantaneously; rather they follow the shortest paths (called geodesics) in curbed or warped spacetime around the massive sun. Thus, according to Einstein, gravity and geometry are the same thing. (Alioto 332)
So to say that our hypotheses are "only" models is not to say that they are useless. It is simply to say - as the logical problems with verifiability and as Popper's own "assymptotic" model suggest, alongside the evidence provided by relativity and quantum mechanics - that in principle we seem unable to "get at" "Truth," at "Reality." This is not so say that all our claims to knowledge are silly illusion and arbitrary: it is to say, in ways suggested by Kant and affirmed by Einstein, that our experience of the world intrinsically involves our own creation of that experience - first of all as our very perspective colors and shapes that experience. Or, to again quote Einstein: "The concepts of theoretical physics need to be correlated with sense-impressions, but in the last analysis concepts are created by the spontaneity of thinking." (Oldroyd 274) But while this may not get us to "Truth" - it nonetheless seems to "work."
- After Popper comes the Sociology of Knowledge school.