The central place of epistemology in modern philosophy is no accident... Knowledge was not a problem for the ruling philosophy of the Middle Ages; that the whole world which man's mind seeks to understand is intelligible to it was explicitly taken for granted. That people subsequently came to consider knowledge a problem implies that they had been led to accept certain different beliefs about the nature of man and about the things which he tries to understand.
No more useful inquiry can be proposed than that which seeks to determine the nature and the scope of human knowledge. ... This investigation should be undertaken once at least in his life by anyone who has the slightest regard for truth, since in pursuing it the true instruments of knowledge and the whole method of inquiry come to light. But nothing seems to me more futile than the conduct of those who boldly dispute about the secrets of nature ... without yet having ever asked even whether human reason is adequate to the solution of these problems.
Can science ever be immune from experiments conceived out of prejudices and stereotypes, conscious or not? (Which is not to suggest that it cannot in discrete areas identify and locate verifiable phenemonena in nature.) I await the study that says lesbians have a region of the hypothalamus that resembles straight men and I would not be surprised if, at this very moment, some scientist somewhere is studying brains of deceased Asians to see if they have an enlarged "math region" of the brain.
Science can only be comprehended epistemologically, which means as one category of possible knowledge, as long as knowledge is not equated either effusively with the absolute knowledge of a great philosophy or blindly with scientistic self-understanding of the actual business of research.
Both social and biosocial factors are necessary to interpret crosscultural studies, with the general proviso that one's research interest determines which elements, in what combinations, are significant for the provision of understanding.
Gilbert Herdt, "Bisexuality and the Causes of Homosexuality: The Case of the Sambia"
The fruitfulness of knowledge indeed plays a role in its claim to truth, but the fruitfulness in question is to be understood as intrinsic to the science and not as usefulness for ulterior purposes.
Max Horkheimer, "Notes on Science and the Crisis," Critical Theory: Selected Essays (1995), p. 3
A modern theory of knowledge which takes account of the relational as distinct from the merely relative character of all historical knowledge must start with the assumption that there are spheres of thought in which it is impossible to conceive of absolute truth existing independently of the values and position of the subject and unrelated to the social context.
Physics is mathematical, not because we know so much about the physical world, but because we know so little: it is only its mathematical properties that we can discover. For the rest our knowledge is negative.
The genius of culture is to create an ontological system so compelling that what is inside and outside of a person are viewed as of a piece, no seams and patches noticable.
Richard Shweder, "Cultural psyschology-What is it?" Cultural Psychology (1990)
Hegel’s lack of charity toward the instrument metaphor is not arbitrary. It represents his disenchantment with the assumption that knowledge is power and that method is the means to this end. ... Descartes’ conception of method, like Bacon’s, is linked to this idea of knowledge as an instrument of power. ... The same could be said of Locke. Hegel can rightly claim that the instrument metaphor pervades the epistemological tradition he is seeking to transcend.
A further turn is to be found in some "unmasking" accounts of natural science, which aim to show that its pretensions to deliver the truth are unfounded, because of social forces that control its activities. Unlike the case of history, these do not use truths of the same kind; they do not apply science to the criticism of science. They apply the social sciences, and typically depend on the remarkable assumption that the sociology of knowledge is in a better position to deliver truth about science than science is to deliver truth about the world.