No. No matter how you try to rationalize it to yourself, you should not have even one cigarette. To do so would put you on the slippery slope that may lead you back into your habit. It appears that prolonged use of nicotine can create a permanent tolerance in the body. This nicotine reaction can be triggered many years after you have quit by smoking a cigarette. It is not worth the risk of becoming hooked to the smoking habit again. All the reasons why you quit are still applicable so why jeopardize this for one cigarette? Just as a recovering alcoholic can never have "just one drink" an ex-smoker should not smoke a cigarette.