(Getting philosophical here. :))
On at least two occasions in the past, while attending morning Srimad Bhagavatam classes at a nearby temple given by two well-known sannyasi gurus, the term "consequentialism" was being explained. Basically, it was said that if we know that an action will produce unfavorable results, we should not act on it. Or as Wikipedia puts it:
"The ethical philosophy, consequentialism is a class of normative ethics, teleological ethical theories that holds that the consequences of one's conduct are the ultimate basis for judgement about the rightness or wrongness of that conduct. Thus, from a consequentialist standpoint, a morally right act (or omission from acting) is one that will produce a good outcome."
The prime example given in both classes was a criticism of Mahajan Bhismadeva for not breaking his vow of perpetual bachelorhood when Satyavati requested he unite with his late brother's wives and later on when Amba requested him to marry her.
But how can one really know whether the result of an action will be good or bad? And if Bhisma had not kept his vow, would he still be as memorable today? Would the battle of Kuruksetra between the Kauravas and the Pandavas really have been avoided? These are some of the questions that arose after the lectures.
And finally answered, for me at least, when this purport came up during my daily reading at home:
"Although Vrtasura was on the verge of defeat (in fighting Lord, Indra), he was not at all affected. He knew that he was going to be defeated by Indra, and he voluntarily accepted that, but since he was supposed to be Indra's enemy, he tried his best to kill Indra. Thus he performed his duty. One should perform his duty under all circumstances, even though one may know what the result will be"