People who knew John Lilly personally, or even just his work, seem to arrive at one of two conclusions: he was either brilliant or crazy. While there is plenty of evidence to support either of these conclusions, it's likely that they are both wrong. Or both are right. Or they are both wrong and right. Or neither is wrong nor right. Or .... This is the way John Lilly looked at things. His first intellectual step was generally to question the terms of the question being asked. Then, after reforming the question, he'd set off on some highly creative and original path toward a whole slew of possible answers.
He was, at various points in his career, a neurophysiologist, biophysicist, computer theorist, dolphin researcher, inventor, drug experimenter, consciousness explorer, and writer. He was the author of ten books, hundreds of scientific articles, and was the prototype for two Hollywood films: Altered States and The Day of the Dolphin.
In Lilly's life, one thing always led to another. After finishing his medical degree, he was one of the pioneers of scientific research using electrical stimulation of the brain. This led him to ponder one of the oldest questions in psychology: is consciousness active or reactive? In other words, in the absence of any stimulation at all from our environment - no sounds, no breeze blowing through the hair, no contact of our skin with the outer world, total darkness and silence ... Would we be conscious? Philosophers had been discussing this question for centuries. But Lilly didn't want to merely discuss this question; he wanted to answer it by experiencing it. So he built a tank that was soundproof, full of very salty body-temperature water (so the body would float easily) - the first sensory deprivation tank (now available by the half-hour to stressed-out executives in every major city).