excerpt from A Defence of Poetry

Reason is the enumeration of quantities already known; Imagination is the perception of the value of those quantities, both separately and as a whole. Reason respects the differences, and Imagination the similitudes of things. Reason is to Imagination as the instrument to the agent, as the body to the spirit, as the shadow to the substance.

NOTES: Reason is the tool of intellect; it has no purpose. Imagination imbues the mind with purpose. The distinction between reason and imagination is akin to the distinction between quality and quantity. We acknowledge the significance of each, all the while holding one in higher regard compared to the other. Reason is a lesser faculty, but it is necessary and instrumental to imagination. Reason implies a mechanical knowledge of things. However, until the imagination allows us to recognize the importance of such facts, they hold no value. It is the soul to the mere vessel of the body. One is inextricably linked with the other.