The object or event identified as the cause of an effect is a genuine cause, but insignificant when compared to the other causes of that event. Note that this fallacy does not apply when all other contributing causes are equally insignificant. Thus, it is not a fallacy to say that you helped cause defeat the Tory government because you voted Reform, for your vote had as much weight as any other vote, and hence is equally a part of the cause.
- Smoking is causing air pollution in Edmonton, so as an environmentalist, you should stop smoking. (True, but the effect of smoking is insignificant compared to the effect of auto exhaust.)
- By leaving your oven on overnight you are contributing to global warming.