Consequentialism it is almost universally misunderstood and so, by extension, is Utilitarianism.
So, to start, let’s clear something up which I believe is at the heart of the matter: Consequentialism is not per se a normative position. Despite what many will have you believe, it is in fact nothing more than a law of ethics – what I would call a meta-ethical truth. In teaching this truth a typical pedagogue tends to explore abstract scenarios, tasking her students to conduct thought-experiments in order to solidify her students understanding, inspire debate and autodidacticism.
Let me attempt to make my point clearer: In the words of Moore, Consequentialism prescribes that “an act is morally right if and only if that act maximises the good, that is, if and only if the total amount of good for all minus the total amount of bad for all is greater than this net amount for any incompatible act available to the agent on that occasion”. The typical pedagogue provides this maxim before then turning to a thought-experiment. For instance, the Trolley Problem:
“Edward is the driver of a trolley, whose brakes have just failed. On the track ahead of him are five people; the banks are so steep that they will not be able to get off the track in time. The track has a spur leading off to the right, and Edward can turn the trolley into it. Unfortunately, there is one person the right-had track. Edward can turn the trolley, killing the one; or he can refrain from turning the trolley, killing the five.” – Judith Thompson
Typically, the students then engage in the thought-experiment – they consider the philosophical implications of the scenario, the ethics of responsibility and will, the distinction between action and inaction, the value of life, explore various definitions of ‘good’ (etc. – etc.) and a plethora of other topics which dress the study of Moral Normativity.
All the while the students subconsciously submit to the assumption that Edward’s unfortunate situation and their related evaluations (or at least aspects of them) are practicable in reality, in Consequentialist terms; they believe that what Consequentialism is telling us about what we ought to do, is to do what is ‘right’. But in doing this they assume a normativity that was never prescribed in the first place (and where other writers may describe the principle as possessing this characteristic, I contend that it should not). And this is where the problem lies.
You see, it is in the nature of such thought-experiments that true answers are only ever discoverable once the boundaries of the envisioned scenarios are absolutely defined. Such thought-experiments describe abstract closed systems wherein, by definition, there exist no spatiotemporal extensions beyond their descriptions. Or in other words, they define all the relevant epistemological factors of a given ethical conundrum. From within, and only from within, these closed systems can Consequentialism be appropriately assumed to have normative value (i.e., be appropriately applied). For, it is only from within closed systems that certainty can be made with respects to the consequences of all the potential optionable actions. When you concern yourself with the Trolley Problem, once you are given all the parameters and provided the rules, when asked about what Edward ought to do, there is only one correct answer. (In our case we are yet to define what ‘good’ means but if we were to adopt a Hedonistic sentiments as Utilitarianism does, the answer would be only to turn right). However, rarely in the real world is there such certainty surrounding the parameters of any ethical situations.
Reality is not a closed system. Or rather, if it is a closed system (in which case it must have a definitive spatiotemporal beginning and end, and be strictly determinate), in the real world we never obtain all the relevant epistemological factors for any ethical situations – possibly besides vacuous ones. Hence, we can rarely, if ever, confidently appropriately apply Consequentialism, trusting that we have strictly conformed to its maxim. Hence, whilst navigating ethical conundrums in the real world, one should rarely attempt to apply Consequentialism in an active sense because in doing so one would invariably contravene the maxim (or put another way, if Consequentialism incorporated a normative characteristic within its maxim, it would be as though it were ordering you always to take the right action whilst never really letting you in on which action is right).
Hence, for the most part, it is only really appropriate to consider Consequentialism as descriptive. It is a meta-ethical truth and nothing much more.
I guess what I’m trying to say is, Consequentialism deserves another run in. But this time we need to understand it and teach it correctly. Otherwise, it’s destined to carry an unjust reputation. As to how it’s compatible with other ethical theories, it’s precisely because it is not normative that it is so. But I’ll leave expounding upon that subject for another rainy day.