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Paul Krugman, Nobel economist, writing about economic modeling, said: "my experience is that many misunderstandings in economics come about because people don't have in their minds any intuitive notion of what it is they're supposed to be modeling."
The same is true in addiction and other areas of psychology and psychopathology when people have no feeling for the crucical psychological and social variables entailed in the phenomenon - like they could explain addiction while having zero sense of how addiction fits into people's make-ups and situations. Given this culture-wide obtuseness, many people assume that we are on the verge of discovering - if we have not already discovered - the cause and nature of addiction in the brain. We have not; we cannot; we will not.
Addiction and human behavior, to state the obvious, do not occur at the molecular level. They require people to act. So, sometimes people decide to smoke a cigarette or have a drink or take drugs, and sometimes they don't. Biological brain models are not good at discerning such decision-making. Perhaps (one day they hope) they can see certain neurons firing when a decision is made - but what decision will be the result?
Think about biological models of smoking addiction, for instance. These are steeped in the neurostatic idea that people must maintain a fixed level of nicotine in their blood systems (they don't, but let's give that to them). Then, one day, someone quits. Perhaps their daughter says to them, "Daddy - don't you love me - why are you killing yourself?"
Neuro-level models have NOTHING to say about such events. Less than nothing for, if you ask neuroscientists, they can only tell you why the person must continue to smoke. There is not a glimpse, a hope, a prayer that they can propose why or when the person actually ceases to smoke. Nor can they then predict when or why, with their circuitry cleared, people do or do not later relapse. Think what such a claim would be - "We saw a bleep on the MRI that made us know he was going to get up and go down to the store and buy a pack of cigarettes."
Here's an experiment you can do at home: Ask some self-assured reductionist, "How would you explain why someone quits smoking because their wife says she won't screw them if they continue?" Listen to them try to filter, somehow, the rewards of sex into a model of nicotine rewards - it's a Rube Goldberg machine that leaves you longing for Freud.
After they've labored like Sisyphus on that one, then ask, "Why might that threat work with one man, but not another - does he like sex with his wife more or less, or find sex more or less rewarding? Does he love her and want to lose her more or less? How does that represent itself in the addictive brain?" As they embark on their new moon launch, throw in - "What if they come from a more romantic culture - where people are more likely to sacrifice everything for love?" Then watch the smoke come out their ears as they whirr their engines!
As with a Goldberg machine, if it takes hours, if it requires unproven speculation after unproven speclation, and if the explainer could just have easily - using exactly the same factors - explained how the exact opposite outcome was assured, then you're not in science land - you're in Uri Gellerville.
