Extraordinary claims have often been made for poetry--Matthew Arnold’s words quoted at the head of this essay are an example--claims which very many people are inclined to view with astonishment or with the smile which tolerance gives to the enthusiast. Indeed a more representative modern view would be that the future of poetry is _nil_. Peacock’s conclusion in his _The Four Ages of Poetry_ finds a more general acceptance. “A poet in our times is a semi-barbarian in a civilized community. He lives in the days that are past ... In whatever degree poetry is cultivated, it must necessarily be to the neglect of some branch of useful study: and it is a lamentable thing to see minds, capable of better things, running to seed in the specious indolence of these empty aimless mockeries of intellectual exertion. Poetry was the mental rattle that awakened the attention of intellect in the infancy of civil society: but for the maturity of mind to make a serious business of the playthings of its childhood, is as absurd as for a grown man to rub his gums with coral, and cry to be charmed asleep by the jingle of silver bells.” And with more regret many others--Keats was among them--have thought that the inevitable effect of the advance of science would be to destroy the possibility of poetry. What is the truth in this matter? How is our estimate of poetry going to be affected by science? And how will poetry itself be influenced? The extreme importance which has in the past been assigned to poetry is a fact which must be accounted for whether we conclude that it was rightly assigned or not, and whether we consider that poetry will continue to be held in such esteem or not. It indicates that the case for poetry, whether right or wrong, is one which turns on momentous issues. We shall not have dealt adequately with it unless we have raised questions of great significance. Very much toil has gone to the endeavour to explain the high place of poetry in human affairs, with, on the whole, few satisfactory or convincing results. This is not surprising. For in order to show how poetry is important it is first necessary to discover to some extent what it is. Until recently this preliminary task could only be very incompletely carried out; the psychology of instinct and emotion was too little advanced; and, moreover, the wild speculations natural in pre-scientific enquiry definitely stood in the way. Neither the professional psychologist, whose interest in poetry is frequently not intense, nor the man of letters, who as a rule has no adequate ideas of the mind as a whole, has been equipped for the investigation. Both a passionate knowledge of poetry and a capacity for dispassionate psychological analysis are required if it is to be satisfactorily prosecuted.