http://nostalgia.wikipedia.org/wiki/Paul_Erdos
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His working habits became characterised by working obsessively long hours, sleeping at most 4-5 hours a night and relying on the heavy use of amphetamines to maintain his activity levels. Once a friend challenged him to give up his drug use for a month; he complied, but later complained bitterly that mathematics was held up for a month.
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Amphetamine is one hell of a drug for productivity but it's got some nasty side effects. It's insane that a very large percent of our children are prescribed hard stimulants. Amphetamine makes just about everyone more productive so of course it makes kids better at school.