What the Brain Does By Itself Is Infinitely More Fascinating and Complex Than Any Response It Can Make To Chemical Stimulation

Ursula K. Le Guin? Elaine Partnow? Apocryphal? Dear Quote Investigator: People have employed psychoactive substances for centuries to pursue alertness, pleasure, insights, thrills, and sundry goals. Yet, a famous speculative fiction author asserted that the brain by itself could achieve infinitely fascinating responses without chemical intervention. Would you please help me to find a citation? …