I'd like for someone to explain to me why the following isn't a sufficient refutation of consequentialism (at least of the maximalist or aggregative variety): One of the more over-reported anecdotes of the past century is Mao's retort to the question, "What was the significance of the French Revolution?" "It's too early to tell," Mao replied. Mao's point was partially tongue in cheek, but it managed to get across an important point: the effects of any action continue on into an indefinite, and at the limit, infinite, future. With that in mind, here's a refutation of consequentialism:
1) The right action in a given situation is a function of its net sum total consequences relative to alternative possible actions.
2) Sum net totals are calculated over total moments.
3) There are no total moments.
4) Hence, there are no sum totals.
5) Hence, there is no net sum total greater than all others.
6) Hence, there is no right action.
The key premise, obviously, is the third. It is also the least refutable. This is the insight captured in Mao's retort, and easily demonstrable: Let's take March 30th, 1794. You are Robesipierre, member the Committee for Public Saftey, deciding on the matter of Danton's execution. You think to yourself, What is the right thing to do? The answer, it is easy to demonstrate, depends upon what time frame is in question (and that, it should be stressed, is solely a matter of whim!). If the time frame is only through the end of the year, killing Danton will exacerbate the reign of terror (leading to your own execution!!), resulting in many more deaths. But, if your time frame is, say, up to 1814, it is precisely the excesses of the Reign of Terror and the Revolution that make Napoleon possible. Napoleon brings order finally to France, but he also harbingers war; yet without Napoleon there is no Congress of Vienna, which brings nearly a century of relative peace to Europe. But of course, without the developments that that century of peace engenders, there is no World War One and thus no World War Two. But without World War Two there is no United Nations....I could go on, but the point I take it is clear: whether it is right for you, Robespierre, to order the execution of Danton right now, in 1794, radically depends upon the time frame in question.
This is not an epistemic point. Of course it is hard to calculate out the consequences, and of course there is no reason whatsoever to believe that Robespierre could have made the considerations I just went over. But that is besides the point, which is that the consequentialist must be a realist about morality. The statement 'It is right in 1794 that Danton be executed' and its opposite, "It is wrong in 1794 that Danton be executed' must each have a determinate truth value. In general, any statement of the sort 'X is right' or 'X is good', if consequentialism is correct, must have a definite truth value, but no statement of that sort does. "It is right that Danton in 1794 be executed" is false in 1795, true in 1814, false again in 1816, true again maybe until 1914, false between 1914 and 1945, true again in 1946, and so on--which is just to say, "It is right that Danton is executed in 1794" has no definite truth value.
I suppose that one could argue that consequentialism is not a normative theory about what one ought to do, but is a descriptive theory that analyzes what we mean by statements of the sort 'X is right' and 'X is good'. But in that case, we have just shown that 'X is right' and 'X is good' have no definite truth values, and this, if any thing, speaks on behalf of error theory--and that, in turn, gets us to the same point: namely, that consequentialism is false.