The ear, the eye, and the brain are not primarily physical things, but symbols that indicate to us the interface of transmutation between the realm of the objective and the subjective (to the extent we even know what that means), and vice versa. Moreover, these symbols are not static, but evolving. This generation’s progress in neuroscience demonstrates how dynamic is our grappling with the question of how it is that we know, and how it is that we are at all. At the same time, it demonstrates how our philosophical, psychological, and material-science understandings constantly bleed together in our acts of considering, theorizing, and knowing.