11 pm. I gave Renfield a strong opiate tonight, enough to make even him sleep, and took away his notebook to look at it. The thought that has been buzzing about my brain lately is complete, and the theory proved.

My homicidal maniac is of a peculiar kind. I shall have to invent a new classification for him, and call him a zoophagous (life-eating) maniac. What he desires is to absorb as many lives as he can, and he has set out to achieve it in a cumulative way. He gave many flies to one spider and many spiders to one bird, and then wanted a cat to eat the many birds. What would have been his later steps?

It would almost be worth while to complete the experiment. It might be done if there were only a sufficient cause. Men sneered at vivisection, and yet look at its results today! Why not advance science in its most difficult and vital aspect, the knowledge of the brain? Had I even the secret of one such mind, if I held the key to the fancy of even one lunatic, I might help my own branch of science.

Vocabulary:

Opiate: A kind of drug
Homicidal: A man-killer
Cumulative: Adding to the additions
Sneer: To make fun of something inferior
Vivisection: Experiments on animals
Vital: Of essential importance
Fancy: Here it means 'strange idea'