Cognitive relativism asserts the relativity of truth, in a way which parallels the way moral relativism asserts the relativity of morality. Because of the close connections between the concept of truth and concepts such as rationality and knowledge, cognitive relativism is often taken to encompass, or imply, the relativity of both rationality and knowledge. The framework, or standpoint, to which truth is relativized is usually understood to be a conceptual scheme or framework. This may be the conceptual scheme of an entire culture or period; or it may be conceived more narrowly as the theoretical framework of a particular community: for example, quantum physicists, or Southern Baptists. Like other forms of relativism, cognitive relativism denies that any of these standpoints enjoy a uniquely privileged status. None of them offer a 'God's eye point of view', or represent the standpoint dictated to us by objective standards of rationality.
Cognitive relativism, like many other forms of relativism, is often said to have been first put forward by the ancient sophists, particularly Protagoras, who began his work 'Truth' with the famous statement: "Man is the measure of all things--of things that are, that they are, of things that are not that they are not.' But with the possible exception of the sophists, few philosophers in the Western tradition have espoused any form of cognitive relativism until relatively recent times. Most assumed that there is some standpoint--for example, that of God--in relation to which our judgments are definitively true or false.
In the nineteenth century this assumption came to be seriously questioned by a small number of important thinkers, most notably Nietzsche and William James. In the twentieth century a relativistic view of truth, although it still provokes vituperative responses from anti-relativists, has undeniably gained many more adherents; indeed, it has become almost commonplace in some philosophical circles. The reasons for this development are diverse. They include:
i) the example offered by relativistic views of moral standards, views which gained in popularity as knowledge of other cultures was extended;Relativistic views of truth have received further impetus from or found expression in the works of many widely read twentieth century thinkers such as the later Wittgenstein, Quine, Kuhn, Winch, Goodman, Rorty, Gadamer, Foucault, and Derrida.
ii) growing awareness, also due to research in anthropology and linguistics, that people in different cultures view the world through radically different conceptual frameworks;
iii) the working out of the full implications of Kant's 'Copernican Revolution' in metaphysics, according to which the objects of our knowledge are shaped by the categories through which we cognize them;
iv) in continental philosophy, the implications--intended or otherwise--of Hegel's historicism, Marx's theory of ideology, and Nietzsche's perspectivism;
v) in English-speaking philosophy, the critique of the positivist philosophy of science, the problems posed by the ideal of objectivity or neutrality in the social sciences, and the impact of discoveries in psychology concerning the interpretation of data.
Cognitive relativists do not simply assert the different cultures or communities have different views about which beliefs are true; no-one disputes that. Nor do they merely claim that different communities operate with different epistemic norms--i.e. criteria of truth and standards of rationality. That, too, seems to be obvious. The controversial claim at the heart of cognitive relativism is that no one set of epistemic norms is metaphysically privileged over any other. This is the claim which non-relativists reject, arguing, on the contrary, that some epistemic norms--for example, those employed by modern science--enjoy a special status in virtue of which they can serve as objective, universally valid, criteria of truth and rationality. Relativists respond to this argument by challenging their opponents to prove the superiority of the epistemic norms they favour. In reply, anti-relativists commonly argue that the success of certain norms in practice--for example, the success of modern science in enabling us to manipulate the world--constitutes a proof that these norms are not just social conventions but really do help us decide which of our judgements are objectively true.
The standard objection to cognitive relativism is that it is self-refuting. If I assert that all judgements are only true relative to some non-privileged standpoint, the objection runs, I am implicitly claiming that this judgement--i.e. the thesis of relativism--is true in some non-relativistic sense. The usual rejoinder by relativists to this objection is a denial that they have to commit themselves to any non-relativistic notion of truth. It is possible, they say, to advance a claim and hold it to be true relative to a given set of norms, without committing oneself to the view that it is true, or that the norms in question are valid, in some further, non-relativistic sense.
A related objection is that the relativist, by his or her own lights, must concede that from some points of view relativism will appear false. Moreover, since no standpoint is uniquely privileged, these standpoints, and the views they encompass or imply, are equally worthy of our respect. The relativist must therefore hold that relativism is both true and false. To this the relativists can reply that while relativism may indeed be false from certain perspectives, these are not perspectives that consistent relativists will be committed to. In fact, they will argue, of those who accept the major paradigm shifts that have characterized philosophy over the last two centuries, relativists can claim to be the most consistent, since they alone accept the full implications of these shifts for our notions of truth and rationality.