James Dewey Watson Quote

The brain is the last and grandest biological frontier, the most complex thing we have yet discovered in our universe. It contains hundreds of billions of cells interlinked through trillions of connections. The brain boggles the mind.

Foreword for Discovering the Brain (1992) by Sandra Ackerman, p. iii; often paraphrased: "The brain is the most complex thing we have yet discovered in our universe."