Utilitarianism: it all went wrong with Sidgwick

The weak philosophical basis of pro-natalism

As part of my critique of pro-natalism, I’m looking at the philosophical foundations of the idea. Most of the explicit discussion takes place within the framework of consequentialism (the idea that the best actions or policies are those with the best consequences) and particularly of utilitarianism, broadly defined to say that the best consequences are those which maximise some aggregate function of individual happiness or wellbeing. Other philosophical traditions either avoid the issue explicitly (for example Rawls’ theory of justice) or offer little that can illuminate debate over population numbers (virtue ethics, contractarian theories).

Looking at the utilitarian analysis immediately creates a puzzle. All the early utilitarians, from Jeremy Bentham to John Stuart Mill supported population limitation. They accepted Malthus’ claim that, in the absence of limitation, population growth would inevitably reduce the great majority of people to subsistence. But unlike Malthus, who used this argument to say that attempts to make the poor better off were futile (he rejected birth control as “vice”) the early utilitarians accepted the desirability of limiting family size.

Most notable among this group was Francis Place. Taking significant legal risks in the repressive climate of the time, Place sought to spread information about contraceptive methods in pamphlets such as Illustrations and Proofs of the Principle of Population (1822).

Importantly, and in contrast to many 20th century Malthusians, Place rejected coercive measures, placing his trust in families to make prudent decisions given access to information and the methods of family planning. Except for his failure (unsurprising at the time) to consider possible conflict within households, Place’s position stands up very well 200 years later.

The classical utilitarians argued for public policies which promoted the welfare of the community to which they applied, on the basis of “each to count for one, and none for more than one”. This contrasted sharply with alternative guides like “national greatness” or “God’s laws”. And, while no philosophical debate is ever resolved, this way of thinking about policy choices (particularly economic policy choices) has remained dominant, or at least influential, down to the present day.

By contrast, contemporary utilitarian philosophy yields bizarre spectacles like “longtermism” which implies that our primary goal should be to produce as many descendants as possible provided that the result is an increase in aggregate utility.

This is far from the only problem with contemporary utilitarian philosophy. It’s commonly presented as a theory of individual ethics, saying that our actions ought to be those which promote the maximal happiness of everyone affected, giving ourselves the same weight as everyone else. Apart from being impossibly demanding, this prescription seems perfectly designed to produce absurd counterexamples (trolley problems, organ kidnapping etc)

Yet another problem is the claim that what matters is the actual outcome of an action, rather than the reasonably expected outcome. The early utilitarians all focused on the general tendency of outcomes, rather than specific outcomes, and this has been formalised by economists with expected utility theory and its various generalisations (my own special subfield of decision theory). But the idea that actual outcomes should be the criterion is promoted by a significant contemporary group drawing on the work of ANU philosopher Frank Jackson.

The task of tracing where and when a tradition of thought has gone off the rails is usually complex and ambiguous. But in this case, the answer is amazingly clear. in 1874, one year after the death of JS Mill (the last of the classic utilitarians), Cambridge philosopher Henry Sidgwick published The Methods of Ethics, which became the standard interpretation of utilitarianism, at least in the philosophical literature

In the space of a few pages, Sidgwick introduced all three of the errors I have criticised above,

First, (Book IV 1.1) he states, “By Utilitarianism is here meant the ethical theory, that the conduct which, under any given circumstances, is objectively right, is that which will produce the greatest amount of happiness on the whole; that is, taking into account all whose happiness is affected by the conduct. ”

Second 1.2 “on Utilitarian principles, population ought to be encouraged to increase, is not that at which average happiness is the greatest possible,—as appears to be often assumed by political economists of the school of Malthus—but that at which the product formed by multiplying the number of persons living into the amount of average happiness reaches its maximum.”

3.3 “It would seem, however, that the ultimate standard of rightness must be the amount of good actually produced, not the amount which was expected to be produced; though we may admit that, in estimating the consequences of actions, we are generally obliged to be guided by the probabilities of different results.”

Sidgwick asserts these points, but doesn’t really argue for them ( “would seem” is doing a lot of work in the third quote, for example). Rather, his style of presentation is tight and rigorous, at least by the standards of 19th century philosophy and his tone is authoritative. The result is that even among philosophical critics, most notably GE Moore, his version of utilitarianism became established as the norm.

Superficially, it might seem that modern social welfare theory has taken Sidgwick’s approach and given it a mathematical formalism. The standard workhorse of this model, the social welfare function, is an aggregate of individual welfare measures, with properties that ensure that the higher the value of the function the better the outcome. But this function is invariably applied in ways that reject Sidgwick’s errors. First, it is used to evaluate public policy, typically in the context of models that do not assume individuals act as disinterest utilitarian ethicists. Second, it is applied to specific fixed populations. Where comparisons are made between populations, they are almost invariably presented in average rather than aggregate terms. And where uncertainty is relevant in evaluating policy, the focus is on expectations over large numbers of cases, not on the actual outcomes in specific cases.

There are plenty of arguments to be made against the utilitarianism of Bentham and Mill. But the starting point for such arguments ought to be a complete rejection of Sidgwick’s errors.

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