So it is that in the fundamental sense, and even, it will have to be added, in a sense that comprehends the extravagancies of wild variations from the norm, we have to recognise that the true man of science is an artist. Like the lunatic, the lover, the poet (as a great physician, Sir William Osler, has said), the student is “of imagination all compact.” It was by his “wonderful imagination,” it has been well pointed out, that Newton was constantly discovering new tracks and new processes in the region of the unknown. The extraordinary various life-work of Helmholtz, who initiated the valuation of beauty on a physiological basis, scientifically precise as it was, had, as Einstein has remarked, an æsthetic colouring. “There is no such thing as an unimaginative scientific man,” a distinguished professor of mechanics and mathematics declared some years ago, and if we are careful to remember that not every man who believes that his life is devoted to science is really a “scientific man,” that statement is literally true.[28] It is not only true of the scientific man in the special sense; it is also true of the philosopher. In every philosopher’s work, a philosophic writer has remarked, “the construction of a complete system of conceptions is not carried out simply in the interests of knowledge. Its underlying motive is æsthetic. It is the work of a creative artist.”[29] The intellectual lives of a Plato or a Dante, Professor Graham Wallas from a different standpoint has remarked, “were largely guided and sustained by their delight in the sheer beauty of the rhythmic relation between law and instance, species and individual, or cause and effect.”[30]