Key word:Pragmatic realism, Rationality, Conceptual relativity, Pragmatism, Indispensability. In his early time, Hilary Putnam was a scientific realist. But now, his philosophical veiw is called by several names, like a ‘internal realism’, ‘pragmatic realism’, or ‘realism with a human face’. He tries to explain not only how the metaphysical realist perspective has broken down in science itself, but also how Rotian relativism fails as an alternative to metaphysical realism. Metaphysical realist insists that a mysterious relation of ‘correspondence’ is what makes reference and truth possible. But Putnam's pragmatic realism is the renuncation of the notion of the ‘things in themselves’ and the notion of correspondence between our words and mind-independent objects. Pragmatic realism says that we don't know what we are talking about when we talk about ‘things in themselves’. It means that the dichotomy between intrinsic properties and properties which are not intrinsic also collapses. Pragmatic realism is willing to think of reference as internal to theories, provided we recognize that there are better and worse texts. ‘Better’ and ‘worse’ themselves depend on our historical situation and our purposes. There is no notion of Gods-Eyes View of Truth here. After all, Pragmatic realism is, at bottom, just the insistence that realism is not incompatible with conceptual relativity. Also Putnam insists that we should not let ourselves fall into either scepticism, scienticism(the idea that science, and only science, describes the world as it is in itself, independent of our perspective) or relativism with respect to our normative judgments, that is, rationality. Logical positivism(scienticism) and relativism fail to take adequate account of the rationality. Logical positivism insists that rationality must be reducible to objective, naturalistic term, while relativism treats rationality as merely subjecitve. But according to Putnam, relativism is self-refuting view like a solipicism, and logical positivism's insistence presupposes normative terms. Putnam illuminates that rationality is value-laden, objective, and purpose-oriented concept. Without this rationality, we have no world and no facts. And these conception of rationality are simply a part of our holistic conception of human flourishing. Putnam's pragmatic realism is under the influnce of American pragmatism. Pragmatism insists that practice has some kind of priority over theory, and everything turns on what sort of priority is claimed. The characteristic of Putnam's pragmatic realism is will to extend the pragmatic approach to the most indispensible area, that is, ethics. So, Putnam illustrates the standpoint of pragmatic realism in ethics by taking a look at some of our moral images.