Walt Whitman spent most of his professional life writing and re-writing Leaves of Grass, revising it multiple times until his death. The first edition was a small book of twelve poems and the last, a compilation of over 400. The poems of Leaves of Grass represent Whitman's celebration of his philosophy of life and humanity. His poetry praises nature and the individual human's role in it. Leaves of Grass (First Edition): Song of Myself A Song for Occupations To Think of Time The Sleepers I Sing ...