I have noticed that in meetings or in pubs people who are smoking seem to be more aggressive (on average, I'm quite an aggressive person myself). My deduction was that nicotine makes people feel cross and tense. I now think I was wrong.
Perhaps nicotine has the opposite effect, calming tension, and so it is selected for self-medication by people who are naturally tense. But, as it has a diminishing effect over time, smokers begin to reassert the general level of anxiety and tension which made them take up smoking in the first place? So I'm seeing tense person/smoking, and making the wrong causal deduction.
All of this may seem either blindingly obvious, or manifestly ridiculous, to smokers. I've never smoked so I know I am ignorant, but I don't think I'm imagining this aggression thing (as a generalisation with exceptions)
