“There are in nature two types or forms, the cell and the crystal. One means the organic, the other inorganic; one means growth, development, life; the other means reaction, solidification, rest.

The hint and model of all creative works is the cell; critical, reflective, and philosophical works are nearer akin to the crystal; while there is much good literature that is neither the one nor the other distinctively, but which in a measure touches and includes both.

But crystallic beauty or cut and polished gems of thought, the result of the reflex rather than the direct action of the mind, we do not expect to find in the best poems, though they may be most prized by specially intellectual persons.

In the immortal poems the solids are very few, or do not appear at all as solids, — as lime and iron, — any more than they do in organic nature, in the flesh of the peach or the apple. The main thing in every living organism is the vital fluids: seven tenths of man is water; and seven tenths of Shakespeare is passion, emotion, — fluid humanity.”

– John Burroughs, (1877)
from his book, “Birds & Poets”