Let us confront the central materialist doctrine that man, like the rest of nature, is made up of matter and nothing more. The best evidence going for this theory is that matter is all we can see, touch, and measure. Moreover, matter seems “responsible” for our thoughts, emotions, and perhaps even our moral intuitions. A powerful blow to the head can cause unconsciousness. Alcohol and fatigue interfere with concentration. Electrical stimulation of certain parts of the brain can produce a desired emotional response. Patients who suffer certain kinds of brain damage lose the capacity to sympathize with others or to recognize shapes. Alzheimer’s disease produces physical deterioration that leads to mental lapse and a complete disappearance of moral awareness.

As consciousness, perception, and thinking all occur in the brain, Francis Crick describes the brain as a conscious, perceptive, and thinking organ. Crick writes, “Both hemispheres can hear what is being said…. What you see is not what is really there; it is what your brain believes is there…. Your brain makes the best interpretation it can…. The brain combines the information … and settles on the most plausible interpretation…. This allows the brain to guess a complete picture.”