By Sam Goldstein ( March 16, 2026, 11:57 AM EDT) -- When a person tells you, “I had a dream last night,” most people understand exactly what that means. The speaker is about to recount the swirl of mental imagery, sounds and emotions experienced during sleep. The story of missing a train, falling from the sky or walking into a classroom naked is not understood as a report of reality but as an account of imagination. Dreams are, almost by definition, the mind untethered from the ordinary constraints of perception and memory. The Spanish surrealist painter Salvador Dalí described dreams as “hand-painted dream photographs.”...