Addiction and

The other way smokers measure their relationship to marijuana is in terms of frequency of use. Here, too, Zinberg and Harding dissent. "You don't expect the once-a-month smoker to be in trouble with the drug," observes Wayne Harding. "And the ten or twenty joint-a-day person probably has a problem But what about the great bulk of smokers in the middle?" The real issue, he insists, is not frequency at all. The real issue is dependence.
    Among marijuana smokers and researchers, dependence is a controversial term. Despite serious attempts to do so, no scientists have been able to demonstrate that marijuana is addicting in human beings or even in animals. Nor does marijuana necessarily lead to larger doses; more commonly, in fact, smokers notice a "reverse tolerance," whereby they find that they can get stoned by smoking less rather than more. Finally, there is no indication that the cessation of marijuana use results in any significant physical effects or problems of withdrawal for the vast majority of smokers.
    This brings us to the issue of "psychological dependence." Marijuana may not be physically addicting, concede its modern opponents; surely, however, it is—or can be—psychologically addicting. But to those who have considered the question, the notion of psychological dependence is meaningless unless it can be shown that marijuana actually causes the dependence. That marijuana can be and is misused by some smokers goes almost without saying; these people can be said to be psychologically dependent on it. But this is different from saying that marijuana is a dependency-inducing drug. As Andrew Weil writes, "Psychological dependence is simply a negative way of describing the behavior of someone who does something repeatedly because he likes it."[3]
    Zinberg and Harding measure dependence among marijuana users by asking smokers not how often they use marijuana but rather what they do when their supply runs out. Harding elaborates:

If a smoker tells me he can't keep the drug around, but has to use it as soon as he gets it, I'd say he's in trouble with it. If a person runs out of pot, I'm not interested in how he feels about it; I want to know what he'll do. I want to know how much discomfort the user will tolerate, and how far he is willing to go to relieve that discomfort. You have to look at it flexibly; after all, many people will walk a dozen blocks to get the Sunday paper, so a certain amount of discomfort has to be expected. I want to know where the marijuana user will draw the line, and whether he will be able to function if he can't get more pot.

    Most smokers, when they run out of marijuana, are able to go without smoking for as long as necessary, with only a minimum of discomfort. If forced to do so by circumstances, many users can abstain indefinitely. A high school student who is concerned about her own dependence on marijuana writes: "It is not so severe as I have heard. The typical user does not go berserk when he is out of grass. He just wishes he had some."
    Indeed, many users, concerned about their relationship to marijuana, and fearful of being dependent on it, will test themselves periodically on their ability to go without smoking. This exercise usually lays to rest any lingering fears about dependency and also, according to some smokers, "cleans out the system." A college student from Maryland speaks for many users:

I smoke daily, because I enjoy it, and not because I feel a need. Well, you might ask, if I smoke every day, how can I be so sure it isn't addicting? Because about a year ago, I stopped smoking for six months. And last summer, when I went on vacation with my family, I didn't get high at all; I didn't even miss it. Through my five years of smoking I have had to stop at different times for various reasons, and never did I feel a craving for it or a panic without it.