Defining Effective Altruism

William_MacAskill19 Jul 2019 10:49 UTC
110 points
22 comments5 min readEA link

Hilary Greaves and Theron Pummer have put together an excellent collection of essays on effective altruism, which will be coming out soon.

Effective altruism is still widely misunderstood in academia, so I took the opportunity to write up my thoughts on how effective altruism should be defined and why, and to respond to some of the most common misconceptions about effective altruism. I hope that having a precise definition will also help guard against future dilution or drift of the concept, or confusion regarding what effective altruism is about. You can find the essay (with some typos that will be corrected) here. Below I’ve put together an abridged version, highlighting the points that I’d expect to be most interesting for the Forum audience and trying to cut out some philosophical jargon; for a full discussion, though, the essay is better.


The definition of effective altruism

I suggest two principal desiderata for the definition. The first is to match the actual practice of those who would currently describe themselves as engaging in effective altruism. The second is to ensure that the concept has as much public value as possible. This means, for example, we want the concept to be broad enough to be endorsable by or useful to many different moral views, but still determinate enough to enable users of the concept to do more to improve the world than they otherwise would have done. This, of course, is a tricky balancing act.

My proposal for a definition (which is making CEA’s definition a little more rigorous) is as follows:

Effective altruism is:
(i) the use of evidence and careful reasoning to work out how to maximize the good with a given unit of resources, tentatively understanding ‘the good’ in impartial welfarist terms, and
(ii) the use of the findings from (i) to try to improve the world.

(i) refers to effective altruism as an intellectual project (or ‘research field’); (ii) refers to effective altruism as a practical project (or ‘social movement’).

The definition is:

  • Non-normative. Effective altruism consists of two projects, rather than a set of normative claims.

  • Maximising. The point of these projects is to do as much good as possible with the resources that are dedicated towards it.

  • Science-aligned. The best means to figuring out how to do the most good is the scientific method, broadly construed to include reliance on careful rigorous argument and theoretical models as well as data.

  • Tentatively impartial and welfarist. As a tentative hypothesis or a first approximation, doing good is about promoting wellbeing, with everyone’s wellbeing counting equally. More precisely: for any two worlds A and B with all and only the same individuals, of finite number, if there is a one to one mapping of individuals from A to B such that every individual in A has the same wellbeing as their counterpart in B, then A and B are equally good.[1]

The ideas that EA is about maximising and about being science-aligned (understood broadly) are uncontroversial. The two more controversial aspects of the definition are that it is non-normative, and that it is tentatively impartial and welfarist.


Effective Altruism as non-normative

The definition could have been normative by making claims about how much one is required to sacrifice: for example, it could have stated that everyone is required to use as much of their resources as possible in whatever way will do the most good; or it could have stated some more limited obligation to sacrifice, such as that everyone is required to use at least 10% of their time or money in whatever way will do the most good.

There are four reasons why I think the definition shouldn’t be normative:

(i) a normative definition was unpopular among leaders of the community; in a survey of such leaders in 2015, 80% of respondents stated that they thought the definition should not include a sacrifice component and only 12.5% thought it should contain a sacrifice component.

(ii) the normative position is endorsed only by a subset of the community; in the 2017 survey of 1843 members of the effective altruism community included the question, ‘Do you think of Effective Altruism more as an “opportunity” or an “obligation”?’ In response, 56.5% chose ‘moral duty’ or ‘obligation’, and 37.7% chose ‘opportunity’ (there was no option in that year to choose ‘both’).

(iii) the non-normative definition is far more ecumenical among moral views. Most plausible moral views would agree that there is some reason to promote the good, and that wellbeing is of some value, and therefore that the question of how one can do the most to promote welfarist value with a given unit of resources needs to be resolved as one aspect of answering the question of how to live a morally good life. In contrast, any sort of claim about our obligations to maximise the good will be much more controversial, particularly if we try to make a general statement covering people of very different income levels and personal situations.

(iv) Finally, it focuses attention on the most distinctive aspect of effective altruism: the open question of how we can use resources to improve the world as much as possible. This question is much more neglected and arguably more important than the question of how much and in what form altruism is required of one.


Effective Altruism as tentatively impartial and welfarist

The second controversial decision is about what we count as ‘the good’ that effective altruism is trying to promote; my proposed definition is tentatively impartial and welfarist.

There is a wide spectrum of alternatives that I could have gone with. On the broad end of the spectrum, we could define effective altruism as the attempt to do the most good, according to whatever view of the good the individual in question adheres to. On the narrow end of the spectrum, we could define effective altruism as the attempt to do the most good on one very particular understanding of the good, such as total hedonistic utilitarianism. Either choice faces severe problems. If we allow any view of the good to count, then white supremacists could count as practicing effective altruism, which is a conclusion that we do not want. If we restrict ourselves to one particular view of the good, then we lose any claim to ecumenicism, and we also misrepresent the effective altruism community itself, which has vibrant disagreement over what good outcomes consist in.

My preferred solution is tentative impartial welfarism, defined above. This excludes partialist views on which, for example, the wellbeing of one’s co-nationals count for more than those of foreigners and excludes non-welfarist views on which, for example, biodiversity or art has intrinsic value. But it includes utilitarianism, prioritarianism, sufficientarianism, egalitarianism, different views of population ethics, different accounts of wellbeing including views on which being able to enjoy art and a flourishing natural environment is partially constitutive of a good life, and different views of how to make comparisons of wellbeing across different species.

This welfarism is ‘tentative’, however, insofar as it is taken to be merely a working assumption. The ultimate aim of the effective altruist project is to do as much good as possible; the current focus on wellbeing rests on the idea that, given the current state of the world and our incredible opportunity to benefit others, the best ways of promoting welfarist value are broadly the same as the best ways of promoting the good. If that view changed and those in the effective altruism community were convinced that the best way to do good might well involve promoting non-welfarist goods, then I’d think we should revise the definition to simply talk about ‘doing good’ rather than ‘benefiting others’.

I believe that this understanding is supported by the views of EA leaders. In the 2015 survey of EA leaders referred to earlier, 52.5% of respondents were in favour of the definition including welfarism and impartiality, with 25% against. So the inclusion of impartial welfarism has broad support, but not as convincing support as other aspects of the definition. And, when we look at all the leading EA organisations, they are firmly focused on promoting wellbeing, rather than promoting non-welfarist sources of value.

What’s more, this restriction does little to reduce effective altruism’s ecumenicism: wellbeing is part of the good on most or all plausible moral views. Effective altruism is not claiming to be a complete account of the moral life. But, for any view that takes us to have reasons to promote the good, and that says wellbeing is part of the good, the project of working out how we can best promote wellbeing will be important and relevant.



[1] Note that, read literally, the use of ‘benefit others’ in CEA’s definition would rule out some welfarist views, such as the view on which one can do good by creating good lives but that this does not involve benefiting those who would otherwise not exist. In this case, philosophical precision was sacrificed for readability.

William_MacAskill19 Jul 2019 10:49 UTC
110 points
22 comments5 min readEA link