There is a constant growth in the value of expressiveness as we ascend the scale of life, expression playing a larger and larger part till with man certain individuals become specialized as expressionists, artists, poets, and orators. Further, fine art is expression which has its value, not in any exterior utility, but in itself alone, the subjective emotion seeking in a manner perfectly free from the common utilities of life to find itself a complete and perfect embodiment. Art here does not serve life, but life, art. The experience has in itself its own vindication for being, in that it expresses. Expression is no longer bare action nor yet a function to serve life, but it becomes a life in itself. In this ideal life of pure expression we recognise the necessity that the expressionist be emancipated from the struggle for existence, be freed from the sordid cares of life, and given up wholly to expressing his individuality with characteristic force; hence the State often pensions writers and artists. But apart from this ideal life, in the evolution of intricate sociality and industry and complex culture, expression becomes a more and more potent factor. Man in society must not only be, he must reveal himself, he must show what he is in order to achieve the most. Many fail, not for lack of faculty, but for lack of expressive ability. Expression, then, in general, is a function which, starting from the most minute beginnings in the lower animals, culminates in man. In large part man is man by reason of his superior power of expression, especially by speech, oral and written. Evolution in man is on the mental side in particular, but a large part of this mentality has been given to the improvement of expression in making it more facile, full and rapid. The complete natural history of expression is yet to be written, and all that I attempt is to indicate the point of view for such an investigation.