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. And, yet, what a great reward one received! How wonderful the whole world became to one! To note the curious hard logic of passion, and the emotional coloured life of the intellect — to observe where they met, and where they separated, at what point they were in unison, and at what point they were discord — there was a delight in that! What matter what the cost was? One could never pay too high a price for any sensation.