Pleasure and Pain

Nature has placed mankind under the governance of two soverign masters, Pain and pleasure. It is for them alone to point out what we ought to do ... .
- Jeremy Bentham, An Introduction to the Principles- of Morals and Legislation (1789)

Is goodness simply a matter of a balance of pleasure over pain?

"Nature," Bentham said, "has placed mankind under the governance of two sovereign masters, pain and pleasure." By this he meant that the only rational way to judge between alternative courses of action is to choose that course which is most productive of pleasure. For example, if my roommate insists I cut the grass, I must ask myself whether I will receive more pleasure from cutting the grass or from continuing to sleep on the sofa. If I cut the grass I will spend an unpleasant hour, but my roommate will be happier and will reward me with kind words, and so on. If I don't, I can enjoy my nap but will wake up to an unpleasant and resentful roommate--no kind words, etc. So I decide to cut the grass.

"Quantity of pleasure being equal," Bentham said, "pushpin is as good as poetry." That meant that goodness is purely a matter of quantity of pleasure. In fact Bentham worked out what he called a "hedonic calculus" in which he assigned numerical values to various pleasures. In the example above I might calculate thus:

Drudgery of cutting grass -5               Joy of having happy roommate +10
( so cutting grass gets a +5)

Pleasure of continuing nap +5              Misery of having unhappy roommate -5
(so not cutting grass gets a 0)

Since the first course of action produces 5 units more of pleasure than the other, I would choose it.[ Considerations of right and wrong seem irrelevant.] But suppose there is a man who gets intense pleasure from drowning cats. How could we persuade hirn, using Bentham's calculus, that he is doing wrong? Pleasure is pleasure, isn't it?

Bibliography

Monro, D.H. "Jeremy Bentham," Encyclopedia of Philosophy, Vol. 1, pp. 280-285, Collier-Macmillan, New York, 1960.

Bentham, Jeremy and John Stuart Mill, The Utilitarians, Garden City, New York, Anchor Books, 1973.