He had been always enthralled by the methods of natural science, but the ordinary subject-matter of that science had seemed to him trivial and of no import. And so he had begun by vivisecting himself, as he had ended by vivisecting others. Human life — that appeared to him the one thing worth investigating. Compared to it there was nothing else of any value. It was true that as one watched life in its curious crucible of pain and pleasure, one could not wear over one's face a mask of glass, nor keep the sulphurous fumes from troubling the brain and making the imagination turbid with monstrous fancies and misshapen dreams.

There were poisons so subtle that to know their properties one had to sicken of them. There were maladies so strange that one had to pass through them if one sought to understand their nature.