Experience and the limits of understanding › The Stakes of a Simple Question

Where does the idea of a triangle come from? You can see particular triangles, but none of them is every possible triangle. And knowing what a triangle means seems different from knowing whether a particular object is in front of you. Locke's *Essay Concerning Human Understanding* separates these questions: where ideas come from, what we do with them, and when their relations amount to knowledge. The familiar image of the mind as a blank slate can obscure that separation. It is tempting to read it as a claim that people have no natural capacities, or that education can make anyone into anything. Neither follows from Locke's rejection of innate ideas. His argument concerns the materials of thought; his account also gives the mind powers for working on those materials. John Locke's *Essay Concerning Human Understanding* argues that sensation and reflection supply our ideas. In Book II, chapter I, he asks us to suppose the mind is like "white paper, void of all characters." The question is how that paper acquires its contents. Experience supplies the materials; the mind subsequently compares and combines them.