There is at least one important issue, which I haven't addressed so far: You have to consider the entire future of the universe in order to make your decision. I shall consider the practical difficulties of this later; there is also a theoretical issue: we are presumably required to add up the total amount of happiness in a person's entire lifetime. So we need some sort of calculus for happiness!
Utilitarianism has the awkward property of seeming entirely obvious to its proponents, and clearly wrong to its opponents.
There are no ethical first principles, which are agreed on by everyone. On the other hand, there is a striking level of agreement about what is actually right and wrong. Of course, there are disagreements. But there is something pretty close to an agreement that (in most cases) murder, lying, rape and theft are bad, and that (in most cases) generosity, healing, truthfulness and loyalty are good.
One obvious thing that these points have in common is that most of the universally agreed “good” things make people happy, and most of the universally agreed “bad” things make people sad.
Furthermore, the actions usually reckoned to be the worst are often the ones that cause the most suffering. Rape, for instance, which causes lasting psychological trauma as well as involving physical injury, is generally reckoned to be morally much worse than theft.
So, utilitarianism seems to do a pretty good job of giving the right answers. It seems clear to me that, all else being equal, something that makes me happy is better than something which doesn't. After all, that's one way in which I make decisions (although I wouldn't in such cases call them moral decisions). Since it seems plausible that all people are ethically equal, this means that anything that makes anyone happy is better than something which does not. This seems to lead naturally to something very like utilitarianism.
However, what I've explained as utilitarianism has a terrible problem: it does not support ethical points in certain cases.
For instance, suppose that I could, by putting my grandmother through tortures, relieve a large number of people from one minute's toothache. No matter how small the amount of suffering from which each person is lifted of, and no matter how great the amount I cause to my grandmother, if the number of people is large enough then the total amount of suffering in the world will be decreased in this manner. Therefore I ought to torture my grandmother. This seems to me, unacceptable. This I see as a major weakness in utilitarianism.
Of course, there are ways round this problem. For instance, we could model happiness and misery with a number system, containing values higher and lower in the sense that no multiple of one was as big as the other.
So, we can get around that particular problem. But, there are others, though I wouldn't claim any of them as an actual rejection of utilitarianism. I shall take the utilitarian principles I listed above, and describe some objections to them.
- Actions, as such, have no moral value. What matters is their effect on the state of the world.
Is this really convincing? It doesn't seem so to me. If I kill someone, isn't there something very bad about that, even if the killing turns out to be right in terms of maximising utility? I think most people would agree that a killing of this sort would be evil.
In fact, the only aspect of life that has any direct moral significance is the happiness or misery of people.
Suppose I tell a lie about you to a friend of mine, who has never had and never will have any sort of interaction with you, and swear him to secrecy, this makes no difference whatsoever to your future happiness. Does that make it OK? It seems clear to me that it doesn't.
Isn't there, in fact, something basically good about truth and bad about falsehood?
Suppose I get enormous satisfaction from causing you minor but genuine unpleasantness. Does that mean that it's right for me to do so?
- In particular, only individuals matter. The only relevance of the state of a family is the effect it has on the individuals.
- All people are, ethically speaking, equal, in all situations. One person's happiness is precisely as important as another's.
What about criminals? If someone is in the process of raping your wife, do you really have to consider their well being as carefully as your wife's in deciding how to go about stopping them?
- It is possible to measure happiness, in the required sense, on some sort of linear scale.
- It is possible to add up different people's degrees of happiness, producing a meaningful "total happiness".
Is it obvious that different sorts of happiness are not easy to measure? How do you compare, the contentment person A has from knowing that his money in the bank is earning him piles of interest for his retirement, the wonder person B feels on looking at the starry sky, the thrill person C has when listening to her favourite piece of music, person D's enjoyment of an evening listening to a stand-up comic, and so on? And how do you weigh those up against person P's toothache, person Q's unhappy marriage? I don't know that's for sure.
Let's pretend that all those problems are resolved, and that I believe that utilitarianism is correct. I now have a decision to make; for instance, I have to decide whether to cycle home in the dark without lights or to be late home. This is a trivial example; it should be easy to work it out. ... Not easy at all. I have to work out the entire future of the whole universe, to work out exactly how happy each person is in each case and for how long, and add it all up. Good grief!
In practice, what the utilitarian recommends is entirely different. I should make guesses as to the likely effects of the actions I'm considering, estimate the ends levels of happiness, and do the best I can at adding them up in my head. Anything more is impossible, and in any case I can't be blamed for things I can't predict.
I'd now like to suggest that there are merits to utilitarianism, despite its drawbacks.
The first point is one I've made already: utilitarianism does a pretty good job of giving answers to ethical questions. Most of us are capable of guessing "what will happen if...” and imagining others' responses to situations.
Also considering "the greatest good of the greatest number" can be an effective way of defeating prejudices and selfishness. This ethical harmony is, after all, quite close to such principles as "Do to others as you would have them do to you" and "Love your neighbour as yourself".
Lastly, I think any theory of ethics has to acknowledge that happiness and suffering are in themselves good and bad. This is why utilitarianism does as well as it does. But clearly happiness and suffering, pain and pleasure, aren't the whole story.
