People do drugs for all kinds of reasons to do drugs — to improve an athletic performance, treat an illness, or, for people in the throes of addiction, because they feel powerless to do otherwise.
But some people — maybe even the majority of recreational drugs users — just do it for fun.
So why is it that pleasure never seems to be part of the conversation around drugs?
Back in 1976 Peter Tosh released his "Legalize It" album, that helped popularise the idea that pot should be legal by emphasizing the medical benefits. Two years later, he expanded his message, suggesting that legalizing pot would boost the Jamaican economy and reduce harm caused by police enforcement.
But a mention of smoking pot for fun is nowhere to be found.
In the early 1990s, Cypress Hill was a little more up front about smoking pot for pleasure, with the release of their album "Black Sunday." But even for Cypress Hill, when it came to seriously advocating for the merits of weed, fun wasn't a big part of the conversation. Instead, the album's liner notes had an itemized list of facts about pot, including its potential benefits of hemp as a source of fibre for creating rope, and even bird seed.
And why does using drugs feel good anyway?
According to Edward Hagen with Washington State University's anthropology department, that question remains a mystery, especially because drugs like tobacco, cocaine and and opium are all dangerous plant toxins.
"It makes sense that we have pleasurable responses to sex and food — both of those are key for survival and reproduction. What was really surprising, about half a century ago, neurobiologists discovered that plant-based drugs activated those same reward mechanisms."
A longstanding, widely accepted account of drugs, is that they are substances we simply didn't evolve to deal with, and that they therefore trigger reward mechanisms in our brain, just by chance.
"The problem with that is that actually we've had a very long exposure to these kinds of substances. And so to us it's relatively implausible that these potent toxins could accidentally trigger a reward mechanism. After all, the last thing a tobacco plant wants to do is encourage herbivores to eat it," said Hagen.
"One hypothesis we've put forward is that although these drugs are very toxic and dangerous to us, they're even more toxic and more dangerous to our parasites."
So there is potential that drugs have some evolutionary benefit — just like sex and food, some plant-based drugs may act as a kind of natural medicine.
According to Carl Hart, the chair of psychology at Columbia University, the failure to acknowledge the pleasurable dimension of why we take drugs is a serious problem, with serious consequences.
"Addiction is a small part of drug use but we act as if it's the largest part," he said. "We have to think of recreational drug use just like the way we think of other psychoactive drugs that are legal, like alcohol. Why do people use alcohol? It's used as a social lubricant. It's used to make people and things more interesting sometimes. Heroin, cocaine, all of these drugs can be used — and are used — in a similar fashion," he said.
Hart said that when we frame all drugs as dangerous, rather than substances that can be used to enhance life, we end up with policies that treat drug use as a problem, ignoring possible benefits.
"I try to get people to focus on the behaviour of interest. And the behavior of interest isn't drug use. It's are those people meeting their obligations and responsibilities? Are they good citizens? Do they treat people well?"
So why do we view alcohol and drugs so differently — and why have we been made to feel so bad about something that feels good?
According to Peg O'Connor, a professor at Gustavus Adolphus College, the answer may lie in philosophy.
Ancient Greek and Roman philosophers enjoyed pleasure — and drew a sharp separation between the soul and body. But religious influences changed that.
"Pleasure starts to get coded, particularly with the rise of the Catholic church and scholastic philosophy, pleasure becomes suspect because it gets tied too closely to the bodily," she said.
This is present in many aspects of culture — from framing certain foods, films, or music as "guilty" pleasures, or in the ways we view people who sacrifice enjoyable aspects of life as strong-willed heroes.
"It's so odd because experiencing pleasure is part of what it means to be human, and yet we've pathologized that and we've moralized against it. But we all seek comfort in certain kinds of ways from the time that we are born."
"Pleasure is always suspect, unfortunately."