Empiricism = the broad view that all knowledge originates from experience.
A problem that Empiricism has had to face is its tendency to lapse into Skepticism
In the 20th century, a group called Vienna Circle aimed to reinvent philosophy in a more scientifically orientated way and established the movement now called Logical positivism or Logical empiricism that was thought to be able to avoid many of the problems faced by traditional empiricism.
Logical empiricism = Any theoretical statement we make about the world around us can be reduced to a statement (or set of statements) about direct experience. For logical empiricism, there is no gap between our talk of material objects and our talk of experience, since our talk of external objects reduces to talk about experience. Logical positivism is best explained by Carnap-logical-analysis-eliminates-metaphysics.
Logical empiricism is an attempt to provide epistemological foundations for the formal sciences (mathematical sciences) and the empirical sciences (the natural sciences).
- Reduction in formal sciences = Logical empiricists try to give a general account of a priori knowledge and believe that mathematics reduces to formal (pure) logic. By formulating appropriate definitions of numerical terms, it can be shown that mathematical truths can be reduced to logical truths.
- Reduction in empirical sciences = logical empiricists attempt to reduce theoretical claims in empirical science to claims about direct experiences, by the method of Ayer-1936-definitions-in-use or as Quine calls it contextual definition.
Analytical/Synthetic statements distinction
analytical sentences = analytic sentences are true or false simply in virtue of the meanings of the term within them. These sentences can be known solely by knowing the meaning of the words. E.G. = “Pediatricians are doctors.”
synthetic sentences = synthetic sentences are true or false in virtue of both the meaning of the words and the way the world is. E.G. = “All pediatricians are rich.”
For Logical empiricism, mathematics and logic is analytical as they do not describe the world. Synthetic claims about the world can use mathematical terms (“Jupiter has 79 moons”) but proof and investigations within mathematics are analytical. According to logical empiricists, the only a priori knowledge are analytical.1
Logical empiricists insists that pure mathematics is analytical, and divided geometry into two parts =
- geometry that describes possible geometrical systems is purely mathematical, and hence analytic
- how geometrical systems apply to our world are synthetic
Verification theory of meaning
Verification theory of meaning = a statement is meaningful (i.e. has factual meaning) only if it is possible (in principle) to empirically verifiable the claim through observations or is a tautology.
Note that this does not require that the sentence itself directly describe observations and it does not not require the observations to provide proof that it is certain that the sentence is true or false.
One main problem within the verifiability principle is that in order to test one claim, you need to test a long complicated conjunction of statements that give you the whole prediction. If a test has an unexpected result, then something in the conjunction is false, but the test itself does not tell where the error is. This is highlighted in Quine-on-the-defects-of-logical-empiricism.
Aim of science according to logical empiricism
Logical positivism was based largely on the theory of language, and claim the aim of science to be able to “track and anticipate patterns in science.”2
For logical positivists, the unobservable structures (e.g. DNA, electrons) in scientific theories are understood as abstracts ways of explaining and predicting observable experience. Logical positivists see scientific theoretical language as a tool and that scientific language is meaningful only if it connects to predictions and captures the “flow of experience” rather than making metaphysical claims about what reality is like in itself.
Criticisms of logical empiricism
- formulating the verifiability principle of meaning
- e.g. = if “metals expand when heating” satisfies the verifiability principle, then the statement “metals expand when heating and the Absolute Spirit is perfect” would also be verifiable because the first part of the statement is verifiable because of the logic criteria of the verifiability principle (based on inductive logic)
- the problem is defining the verifiability principle of meaning in a way that that excludes metaphysics while including theoretical principles used in science.
- logical focus too limited = neglects history of science, values of science
- theories are tested holistically
- another problem of the verifiability theory is the holism property about theory testing that it is not possible to test a single statement in isolation; a theory is tested as a whole
- untenability of the analytic-synthetic distinction
- Quine’s argument against logical empiricism = Quine-on-the-defects-of-logical-empiricism
“It is obvious that truth in general depends on both language and extralinguistic fact. The statement ‘Brutus killed Caesar’ would be false if the world had been different in certain ways, but it would also be false if the word ‘killed’ happened to rather to have the sense of ‘begat’. Thus one is tempted to suppose in general that the truth of a statement is somehow analyzable into a linguistic component and a factual component. Given this supposition, it next seems reasonable that in some statements the factual component should be null; and these are the analytic statements. But, for all its a priori reasonableness, a boundary between analytic and synthetic statements simply has not been drawn. That there is such a distinction to be drawn at all is an unempirical dogma of empiricists, a metaphysical article of faith”
- Quine, “Two Dogmas of Empiricism” p. 36
The statement “Brutus killed Cesar” could be false in two ways = Factual failure (if Brutus didn’t kill Cesar), or linguistic failure (if the word “killed” meant “begat”). From this observation, one could conclude that truth = linguistic component + factual component and that some statements have both components (synthetic) and some statements have only a linguistic component (analytic). This is logical empiricist’s intuition.
Quine criticizes that “a boundary between analytic and synthetic statements have simply not been drawn.” Any attempt Carnap makes to define analytic statements ends up presupposing exactly what it is supposed to explain; there seems to be no clear line between truths grounded in language and truths grounded in fact. Quine argues that logical empiricism rests on a non-empirical metaphysical assumption