It is very easy to commit a gross fallacy here. This is to confuse the two statements "the motive m frequently leads to bad results" and "the frequency of the motive m would lead to bad results." From the former we could conclude that any particular instance of the motive is likely to lead to bad results; from the latter we can conclude nothing of the sort.
(C. D. Broad, "On the Function of False Hypotheses in Ethics," The International Journal of Ethics 26 [April 1916]: 377-97, at 396)
Keith Burgess-Jackson, J.D., Ph.D. 