Apparently marijuana and LSD were the big ones among geniuses, and some may surprise you...

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10 Geniuses Who Used Drugs -- And Their Drugs of Choice

Is intelligence related to an increased likelihood of recreational drug use?

Source: Alternet

It's an interesting hypothesis, and one that's been gaining momentum in recent years.

If a definitive link between intellectual capacity and drug use does exist, it will likely be some time before anyone establishes one. Having said that, this much is for certain: history has more than its fair share of experimenting experimentalists. Let's meet 10 of history's most influential scientific and technological visionaries, along with their drugs of choice.

Francis Crick — LSD
Francis Crick — of the DNA-structure discovering Watson, Crick, and Franklin — reportedly told numerous friends and colleagues about his LSD experimentation during the time he spent working to determine the molecular structure that houses all life's information.

In fact, in a 2004 interview, Gerrod Harker recalls talking with Dick Kemp — a close friend of Crick's — about LSD use among Cambridge academics, and tells the Daily Mail that the University's researchers often used LSD in small amounts as "a thinking tool." Evidently, Crick at one point told Kemp that he had actually "perceived the double-helix shape while on LSD."

Thomas Edison — Cocaine Elixers
In 1863, French chemist Angelo Mariani invented "Vin Mariani," a Bordeaux wine treated with coca leaves, the active ingredient of which is none other than cocaine. The ethanol content in the Bordeax could extract cocaine from the coca leaves in concentrations exceeding 7mg per fluid ounce of wine. Thomas Edison — the prolific American inventor and notorious insomniac (though perhaps not surprisingly) — was one of many people of the period known to regularly consume the cocaine-laced elixir.

Steve Jobs — LSD
LSD was a big deal for Steve Jobs. How big? Evidently, Jobs believed that experimenting with LSD in the 1960s was "one of the two or three most important things he had done in his life." What's more, he felt that there were parts of him that the people he knew and worked with could not understand, simply because they hadn't had a go at psychedelics. This latter sentiment also comes through in his recently-published biography, wherein Jobs goes so far as to associate what he interpreted as Bill Gates' dearth of imagination with a lack of psychedelic experimentation:

"Bill is basically unimaginative and has never invented anything, which is why I think he's more comfortable now in philanthropy than technology. He just shamelessly ripped off other people's ideas."

"He'd be a broader guy," Jobs says about Gates, "if he had dropped acid once or gone off to an ashram when he was younger."

Bill Gates — LSD
Which is funny, because Bill Gates totallydidexperiment with LSD, though an excerpt from a 1994 interview with Playboy reveals he was much less open about it than Jobs:

PLAYBOY: Ever take LSD?
GATES: That was on the other side of that boundary. The young mind can deal with certain kinds of gooping around that I don't think at this age I could. I don't think you're as capable of handling lack of sleep or whatever challenges you throw at your body as you get older. However, I never missed a day of work.

John C. Lilly — LSD, Ketamine
Neurocientist John C. Lilly was a pioneer in the field of electronic brain stimulation. He was the first person to map pain and pleasure pathways in the brain; founded an entire branch of science exploring interspecies communication between humans, dolphins, and whales; invented the world's first sensory deprivation changer; and conducted extensive personal experimentation with mind-altering drugs like LSD and ketamine.
It bears mentioning that Lilly's experiments with interspecies communication, personal psychedelic use, and sensory deprivation often overlapped.

Richard Feynman — LSD, Marijuana, Ketamine
Feynman was always careful about drug use, for fear of what it might do to his brain — giving up alcohol, for example, when he began to exhibit symptoms of addiction. InSurely You're Joking, Mr. Feynman!, he writes, "You see, I get such fun out of thinking that I don't want to destroy this most pleasant machine that makes life such a big kick. It's the same reason that, later on, I was reluctant to try experiments with LSD in spite of my curiosity about hallucinations."

Nevertheless, Feynman's curiosity got the best of him when he became acquainted with none other than John C. Lilly and his sensory deprivation tanks. Feynman experimented briefly with LSD, ketamine, and marijuana, which he used to bring on isolation-induced hallucinations more quickly than he could when sober.

Kary Mullis — LSD
Who, you may be asking, is Kary Mullis? Let's put it this way: If you've worked in a biomedical research lab since the 1980's, there is an exceedingly good chance you've performed a polymerase chain reaction (aka PCR, the lab technique that can turn a single segment of DNA into millions of identical copies), or are at least familiar with it. You have Mullis to thank for that. While Mullis didn't invent the PCR technique, per se, he improved upon it so significantly as to revolutionize the field of biomedical research,securing himself a Nobel Prize in chemistryin the process.

The secret to Mullis' breakthrough? In a September, 1994 issue of California Monthly, Mullis says that he "took plenty of LSD" In the sixties and seventies, going so far as to call his "mind-opening" experimentation with psychedelics "much more important than any courses [he] ever took." A few years later, in an interview for BBC's Psychedelic Sciencedocumentary, Mullis mused aloud: "What if I had not taken LSD ever; would I have still invented PCR?" To which he replied, "I don't know. I doubt it. I seriously doubt it."