Mind–body problem

“We must no more ask whether the soul and body are one than ask whether the wax and the figure impressed on it are one.”

“People often prefer to believe that there is a disembodied soul that, in some utterly mysterious way, does the actual seeing, helped by the elaborate apparatus of the brain. Some people are called "dualists"—they believe that matter is one thing and mind is something completely different. Our Astonishing Hypothesis says, on the contrary, that this is not the case, that it's all done by nerve cells. What we are considering is how to decide between these two views experimentally.”

“Dualism makes the problem insoluble; materialism denies the existence of any phenomenon to study, and hence of any problem.”

“Men believe themselves to be free, simply because they are conscious of their actions, and unconscious of the causes whereby those actions are determined.”

“What is conserved, in modern physics, is not any particular substance or material but only much more abstract entities such as energy, momentum, and electric charge. The permanent aspects of reality are not particular materials or structures but rather the possible forms of structures and the rules for their transformation.”