Wilfrid Stalker Sellars was an American philosopher and prominent developer of scientific realism and critical perceptual realism who "revolutionized both the content and the method of philosophy in the United States". His work has had a profound impact in virtually all areas of analytic philosophy beginning in the latter half of the 20th century, including in epistemology, philosophy of language, philosophy of mind, philosophy of perception, and philosophy of science. His most notable contributions include his critique of foundationalist epistemology, a synoptic philosophy aiming to unite what he called the manifest and scientific images, and an inferentialist account of meaning.