I cannot anyhow be contented to view this wonderful universe, and especially the nature of man, and to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe what he can.

It is curious to reflect on how history repeats itself the world over. Why, I remember the same thing was done when I was a boy on the Mississippi River. There was a proposition in a township there to discontinue public schools because they were too expensive. An old farmer spoke up and said if they stopped the schools they would not save anything, because every time a school was closed a jail had to be built.
It's like feeding a dog on his own tail. He'll never get fat. I believe it is better to support schools than jails.

Since Pawlow [Pavlov] and his pupils have succeeded in causing the secretion of saliva in the dog by means of optic and acoustic signals, it no longer seems strange to us that what the philosopher terms an 'idea' is a process which can cause chemical changes in the body.

The laboratory was an unattractive half basement and low ceilinged room with an inner dark room for the galvanometer and experimental animals. It was dark, crowded with equipment and uninviting. Into it came patients for electrocardiography, dogs for experiments, trays with coffee and buns for lunch. It was hot and dusty in summer and cold in winter. True a large fire burnt brightly in the winter but anyone who found time to warm his backside at it was not beloved by Lewis. It was no good to try and look out of the window for relaxation, for it was glazed with opaque glass. The scientific peaks were our only scenery, and it was our job to try and find the pathways to the top.

Visualize yourself confronted with the task of killing, one after the other, a cabbage, a fly, a fish, a lizard, a guinea pig, a cat, a dog, a monkey and a baby chimpanzee. In the unlikely case that you should experience no greater inhibitions in killing the chimpanzee than in destroying the cabbage or the fly, my advice to you is to commit suicide at your earliest possible convenience, because you are a weird monstrosity and a public danger.

What a weak, credulous, incredulous, unbelieving, superstitious, bold, frightened, what a ridiculous world ours is, as far as concerns the mind of man. How full of inconsistencies, contradictions and absurdities it is. I declare that taking the average of many minds that have recently come before me ... I should prefer the obedience, affections and instinct of a dog before it.