On "Empiricism and the Philosophy of Mind" (1956). Is knowledge based on a "foundation," as Descartes, Locke, et al. thought? Sellars says no. Sixteenth-century empiricists thought that we have some indubitable perceptions: Even though I may not be absolutely sure that there's a red object in front of me, I can be sure that there seems to be such an object. The "red  Continue Reading …