In philosophy, one of several metaphysical theories, many of which are not mutually compatible. Straight metaphysical realism is the view, roughly, that there exist mind-independent objects. It is often associated with a correspondence theory of truth, that is, that there is a correspondence between pieces of knowledge and their objects.

This theory is opposed by Hilary Putnam's internal realism, which has undergone revision several times (or at least been variously presented by Putnam), and is the view that no correspondence theory is required for a sound epistemology (or is even possible).

In addition to these two, there is also the so-called "common-sense" realism. According to this theory, the things we see, such as tables, chairs, and elephants, are just real. This isn't all just a dream. The questions the first two theories attempt to answer are considered pointless under this view.

All three realisms are in opposition to various antirealistic theories, including several which together are labeled relativism.