Coruscation

"Bing" is a word that Stuart Hameroff, the University of Arizona professor who organizes these mindfests, uses to describe the moment when the spark of consciousness lights up the brain. Imagine a mad scientist hooking together neurons one by one until suddenly they reach a threshold of complexity and -- bing -- consciousness emerges.

We all know the feeling, one that science has been powerless to explain. The audience seemed familiar enough with the words, and so they sang along in 4/4 time.

Before launching into the tune, Timbre Wolf played a recording of an eerie composition called "Brain Dance," derived from vibrations generated by tiny molecular structures called microtubules, which are part of the scaffolding of brain cells. The music, to his ear, was reminiscent of Philip Glass, Steve Reich, Cuban rumba, Gustav Holt's "The Planets," and the visual rhythms of strange mathematical objects called Penrose tiles.

All of this, he suspected, had something to do with quantum mechanics and consciousness, an idea that Dr. Hameroff has long been pursuing.

There even seemed to be undertones of the Devil's Triad, a discordant combo of notes known since medieval times that forms the opening riff of "Purple Haze."

That all made for good metaphysical fun. More disconcerting was the starring role given to the New Age entrepreneur Deepak Chopra. Dr. Chopra believes that human consciousness (through epigenetic feedback) directs the unfolding of human evolution.

No one seemed to object as Dr. Chopra, whose Chopra Foundation was one of the sponsors, shared the stage with prominent professors who engaged with his ideas as if he were another esteemed colleague.

But that's how it is at Tucson. There were talks on psychic phenomena and retrocausality, the hypothesis that the future can affect the past through quantum emanations. Presentations that didn't make it into prime time were laid out in colorful posters attached to rows of bulletin boards: "What Might Cause a Star's Consciousness?" "The X-Structure: The Basic Nature of Life and Existence."

Also included in the lineup were presentations hypothesizing that dark energy could explain consciousness and that homeopathic medicine might work through nanoparticles and quantum entanglement -- as if homeopathy worked at all.

Beyond all of that, there was still plenty of serious theorizing. For a rapid-fire summary, you can hear Baba Brinkman, a rap artist who provided a daily report on the meeting, which he called "half science lab and half Burning Man."

Late one night at an event called Club Consciousness, Mr. Brinkman joined Dorian Electra and the Electrodes as the band regaled the crowd with songs like "Mind-Body Problem" (a reference to the age-old question of how something as seemingly ethereal as consciousness emerges from the brain) and "Brain in a Vat" (the idea that for all you know, you're just a brain kept alive in a laboratory flask and what seems like reality is an illusion).

"Chinese Room" was about a thought experiment that the philosopher John Searle claims to be a refutation of the possibility of artificial intelligence. But the big hit of the night, "Sensual," which has been made into a rock video, was about a famous intellectual conflict that has raged since the 17th century when John Locke went to the mat with René Descartes over the source and nature of human knowledge.