(1) BELIEFS are the primary way we represent the world to ourselves, // (2) knowledge is something like justified, true, BELIEF (plus maybe some fourth condition added), // (3) the propositional content of a BELIEF is determined by whatever it is in the world that makes the belief true or false, // (4) a BELIEF is a kind of attitude someone has to a proposition (where propositions are linguaform), // (5) BELIEFS are caused by perception, reason, and other BELIEFS, // (6) BELIEFS and desires cause actions including: (a) in suitable situations assertions of sentences with the propositional content of the belief, and (b) given the BELIEFS one has, rational attempts to fulfill desires, // (7) One has privileged access to what one believes, in the strongest sense this means that one can know what one believes by introspection, // (8) the most important information in judging people is the set of BELIEFS they have, // (9) the most important factor in becoming the proper kind of person, is yourself having the proper set of BELIEFS, // (10) it is rational as a principle of social organization that people group themselves in terms of what they BELIEVE.
Frege conclusively proved that (3) as stated is false. His argument gave rise to two problems: (i) stating what the content of the belief is (i.e. sets of possible worlds, verification conditions, structured propositions, etc.), and (ii) informatively characterizing the identity conditions of such contents such that a plausible logic of beliefs can be discerned. (2) is so difficult that it’s unsolvability may be a philosophical datum at this point.
Arguably (with creative readings of Heidegger and Wittgenstein) (1)-(5) give rise to the problem of the external world and the rule-following paradox.
Freud noted correctly that (6a) and (6b) conflict in many cases, and concluded from this correctly that we should thus reject (7). Unfortunately, he then theorized incorrectly that in such cases the subject had determinate unconscious BELIEFS. Sartre’s arguments about the unconscious, Mark Wilson’s (Wittgensteinian) arguments about the underdetermination of content, Hilary Putnam’s ingenious misinterpretation of Quine in articles such as “Meaning Holism,” (and to a lesser extent, Putnam’s “The Meaning of Meaning” article), together obliterate the Freudian idea that the postulation of an unconscious believer’s determinate beliefs is either true or helpful.
Sartre, Wilson, and Putnam also show that (3) and (4) are false as explicated by most philosophers (albeit perhaps true if properly understood).
Since Aristotle, reflective people have rejected (8) and (9). Sartre and the psychological behaviorists made this rejection the cornerstone of much of their (actually quite similar) philosophy. For both we are what we do, not what we might be described as believing. In the context of religious practice, John Whittaker argues persuasively that a focus on propositional (meaning some combination of the above) belief in the ways adumbrated in (8)-(9) leads to hypocrisy (characteristic misalignment between 6a and 6b), and violent intolerance. [If I understand right, Whittaker would characterize religious people’s statements that they believ in a non-cognitivist fashion, whereas I would argue that (again propositional) belief is the enemy of faith. This may not be a difference that makes a difference though. In either case, I’m convinced that he has an adequate reply to Ed Henderson’s smart critique that religious people would reject his construal of their practice. Whittaker (and myself, though I’m not able to make the case nearly as well as he can) can point to the contemplative traditions in all faiths to find strong support for non-propositional belief construals of religious practice.]
(10) is the cause of immeasurable suffering.
Some of Marx, Nietzsche, and Foucault’s main arguments can be stated in terms of how they effect (1)-(10) as well.