On a remarkably thin base of evidence – largely the spectral analysis of points of light – astronomers possess, or appear to possess, an abundance of knowledge about the structure and history of the universe. We likewise know more than might even have been imagined a few centuries ago about the nature of physical matter, about the mechanisms of life, about the ancient past. Enormous theoretical and methodological ingenuity has been required to obtain such knowledge; it does not invite easy (...) discovery by the untutored. It may seem odd, then, that we have so little scientific knowledge of what lies closest at hand, apparently ripe for easy discovery, and of greatest importance for our quality of life: our own conscious experience – our sensory experiences and pains, for example, our inner speech and imagery, our felt emotion. Scientists know quite a bit about human visual capacities and the brain processes involved in vision, much less about the subjective experience of seeing; a fair bit about the physiology of emotion, almost nothing about its phenomenology. Philosophers began in earnest in the seventeenth and eighteenth centuries to describe and classify our patterns of conscious experience. John Locke, for instance, divided experienced “ideas” into those that arise from sensation and those that arise from reflection, and he began to classify them into. (shrink)