“No,” he said, “that can’t be done. That is to say, one hasn’t a free will, even if the person acts that way. Neither can the other person think as he will, nor can I make him think what I want him to. But you can observe someone well, and then you can say fairly exactly what he thinks or feels; in this way you can generally predict what he will do the moment after. It’s quite simple, but people merely do not know it. Naturally it requires practice. To take an example from the butterfly world, there is a certain species of moth, of which the female is much rarer than the male. The moths reproduce like other animals, the male impregnates the female, who then lays the egg. Suppose you have in your possession a female of this type of moth⁠—naturalists have often made the experiment⁠—then the male moths fly in the night to this female, they even make a flight of several hours’ duration! Think of it! For many miles around all the males are conscious of the whereabouts of the only female moth in the district. People have tried to explain that, but it is not easy. Moths must have a sense of smell, or something like it, which allows them to pick up and follow an almost imperceptible scent, like a good hound. You understand? There are such things, nature is full of them, and no one can explain them.