‘We would add,’ says the writer of the article in the _British Medical Journal_, ‘that the intelligent application of the physician’s knowledge of the influence of the body on the mind is the one condition of success in the difficult art of dealing with patients and reinforcing the curative power of Nature or, what comes to the same thing, enabling sufferers to work out their own deliverance from the thraldom of functional disease. All really great physicians have used this force, sometimes, it may be, unconsciously, but often with deliberate intent. It is the power of influencing the mind of the patient or, in other words, of exciting confidence in his gift of healing, that makes what is called “personal magnetism.”’ At this point I may be permitted to offer one or two observations. (1) To speak quite strictly, it is not a question of _‘à priori’ possibility or impossibility_. As Huxley pointed out, twenty years ago, few things can be said to be _impossible_ except mathematical misstatements or manifest contradictions. Thus 2 + 2 cannot possibly yield any result but 4. A square circle, a raised depression, are, in the strictest sense of the term, _impossibilities_. But, with regard to an enormous number of alleged phenomena popularly styled _impossible_, what is really meant is either that they are not impossible at all, but only in some high degree improbable, or that we have not sufficient knowledge to enable us to say whether or not they are impossible. In any case, before accepting them, we are bound as honest men to demand evidence which may be thoroughly sifted. The sort of stuff which we usually get, when we ask for such evidence, will be instanced at a later stage.