In What is Poetry, John Stuart Mill presents the idea that poetry is not defined by the form it takes, but from how it is derived. Poetry, for Mill is the opposite of fact or science. It is a reflection of the soul, of human emotions. A poet must describe things “as they appear, not as they are.” Truth in poetry is to be found, for Mill, in how honestly the poet expresses his feelings about his subject. He is not expected to express honestly what the subject exactly was, or looked like.
For John Ruskin, however, the subject is what should be portrayed truthfully, and feelings only impede upon the poet’s ability to do this. Emotions cause us to react to things irrationally, and describe thing exaggeratedly. Poetry, to Ruskin, must be rational and realistic in order to be great. The great poet “perceives rightly in spite of his feelings.” Ruskin distrusts emotions, and seems happy to ignore them altogether, in order to see the world in a way that he believes to be truthfully.
Then Walter Pater comes along, and continuing along Mill’s train of thought, takes his idea one step further and says that poetry leads to feeling. Pater speaks from the critic's, or even just the reader's point of view. He asks us to pay attention to how an object of beauty can makes us feel. He believes that “Beauty, like all other qualities presented to human experience, is relative.” And so it is important for us to realise why something may be so beautiful to us, and why it stimulates this particular reaction. He says: “…the first step towards seeing one’s object as it really is, is to know one’s own impression as it really is…”.
Pater sees it as vital to stop and recognize why we have the reactions, emotional or otherwise, we do to art. We must fully appreciate all our life experiences: “For our one chance lies in expanding that interval, in getting as many pulsations as possible into the given time.”