Top Highlights

• The influential German Enlightenment philosopher Immanuel Kant famously argued that we have no direct access to reality; we may perceive the world a certain way because it is the only way we can perceive it.
• There’s no generally accepted term for the relation between first- and third-person perspectives, or for their failure to align—which is strange, because philosophers love naming things. I’ll call it the “inside/outside problem.” It is one aspect of the subject known as epistemology.
• By analogy, at a concert you may think you are clapping in time with the music, but the drummer may think your rhythm is off—and both of you may be right, because sound takes time to travel. An absolute notion of “simultaneous” presumes an unattainable God’s-eye view. To make progress, we have to let it go.
• The qualities of experience, known as “qualia” (“quale” in the singular), can’t be grasped intellectually. They must be experienced firsthand.
• “Perception and that which depends on it cannot be explained mechanically, that is, by means of shapes and motions,” the German philosopher Gottfried Leibniz wrote in 1714. “And if we suppose that there were a machine whose structure makes it think, feel, and have perception, we could imagine it increased in size while keeping the same proportions,...