We recruited 367 current daily smokers via the Internet and randomized them to rate the causes of an inability to stop smoking, inability to stop problem alcohol use, or inability to lose excess weight in a fictional scenarios. Most smokers attributed inability to stop smoking to addiction (88%), habit (88%) and stress (62%). Surprisingly, equal numbers of smokers agreed and disagreed that inability to stop smoking was due to lack of willpower or motivation. Most disagreed that it was due to biological factors, denial, family/upbringing, genetics, mental disease, personality problem, psychological problems, or weakness of character. Many expected correlations among perceived causes were not found; e.g. endorsement of addiction was not inversely related to endorsement of willpower. Most smokers endorsed treatment. Higher ratings of addiction were related to endorsing treatment, and higher ratings of motivation were related to endorsing no need for treatment; however, these relationships were of small magnitude. Ratings of almost all the causes varied across the three problems; e.g. ratings of addiction were greater for smoking than for problem alcohol use. In summary, smokers appear to view the inability to stop smoking as multicausal; however, their views of causes are only weakly related to attitudes towards treatment. Given the several unexpected findings, qualitative research into smokers' conceptualizations about smokers' inability to stop smoking is indicated.