"Now, what I want is to give to my investigation the precision of a mathematical demonstration--I want my conclusions to be as plain, as indisputable, as that twice two are four. Now, supposing I have this gentleman arrested prematurely, though I may be positively certain that he is _the man,_ yet I deprive myself of all future means of proving his guilt. How is that? Because, so to say, I give him, to a certain extent, a definite status; for, by putting him in prison, I pacify him. I give him the chance of investigating his actual state of mind--he will escape me, for he will reflect. In a word, he knows that he is a prisoner, and nothing more. If, on the contrary, I take no kind of notice of the man I fancy guilty, if I do not have him arrested, if I in no way set him on his guard--but if the unfortunate creature is hourly, momentarily, possessed by the suspicion that I know all, that I do not lose sight of him either by night or by day, that he is the object of my indefatigable vigilance--what do you ask will take place under these circumstances? He will lose his self-possession, he will come of his own accord to me, he will provide me with ample evidence against himself, and will enable me to give to the conclusion of my inquiry the accuracy of mathematical proofs, which is not without its charm. "If such a course succeeds with an uncultured moujik, it is equally efficacious when it concerns an enlightened, intelligent, or even distinguished man. For the main thing, my dear friend, is to determine in what sense a man is developed. The man, I mean, is intelligent, but he has nerves which are _over_-strung. And as for bile--the bile you are forgetting, that plays no small part with similar folk! Believe me, here we have a very mine of information! And what is it to me whether such a man walk about the place in perfect liberty? Let him be at ease--I know him to be my prey, and that he won't escape me! Where, I ask you, could he go to? You may say abroad. A Pole may do so--but my man, never! especially as I watch him, and have taken steps in consequence. Is he likely to escape into the very heart of our country? Not he! for there dwell coarse moujiks, and primitive Russians, without any kind of civilization. My educated friend would prefer going to prison, rather than be in the midst of such surroundings. Besides, what I have been saying up to the present is not the main point--it is the exterior and accessory aspect of the question. He won't escape--not only because he won't know where to go to, but especially, and above all, because he is mine from the _psychological_ point of view. What do you think of this explanation? In virtue of a natural law, he will not escape, even if he could do so! Have you ever seen a butterfly close to the candle? My man will hover incessantly round me in the same way as the butterfly gyrates round the candle-light. Liberty will have no longer charms for him; he