Emotions color the line drawings with which cognition represents reality. The philosophical distinction between the cognitive sense and private feelings can be traced back to Aristotle; it continues to our day in the concept of objective scientific knowledge. We take emotions to be distinctively human phenomena. Outside the crystal ball of the human psyche, there are only grass that does not wince when we tread on it, trees that are impassive as the chain-saw slashes them, water that does not shiver with pleasure when we stroke it, atoms drifting through the void without anxiety and colliding without pleasure or pain. If these things move us, it is because we are moved by the colors we project onto them. All colors, according to John Locke and seventeenth-century epistemology, including the “color” of emotion, are subjective effects within the pscyhe of the viewer.