The most significant aspect of the DNA story is that the fundamental processes of life now seem fully understandable in terms of physics and chemistry. No life force, no spirit, no soul seems to be involved. Likewise in neurophysiology: Tentatively, the mind seems to be the expression of the hundred trillion neural connections in the brain, plus a few simple chemicals.

— Carl Sagan Billions and Billions: Thoughts on Life and Death at the Brink of the Millenium (1997)

More quotes by Carl Sagan

Cosmos (1980)

Cosmos (1980)

Cosmos (1980)

Contact (1985)

The Demon-Haunted World : Science as a Candle in the Dark (1995)

Quote text and notes from Wikiquote: Carl Sagan (page history), available under CC BY-SA 4.0. Source quality and labels are our own summary of what Wikiquote records.