Cross posted at
This text grew out of discussions with some of EA global planners, many previous discussions with individuals considering if they want to identify as EAs and strategic considerations scattered around many EA articles. It is particularly related to Helen Toner's Effective Altruism is a question, not an ideology.

A confusion I hear frequently from new EAs working on movement building takes the following form: 

1) Effective Altruism is a movement

2) Other movements have done this or that (say, accelerate movement growth using this technique X), should Effective Altruism be doing the same?

3) Other movements failed in thing Z and now most people in them are not sane, how can we avoid this?

These claims and questions rest on a reference class assumption that is false. 

It is false that the reference class to reason about Effective Altruism is the movements class.

Not all movements are made alike. Although EA has many movement characteristics, such as growth rates, core groups, a need to mobilize people, some epistemic and value alignment, a desire to grow, a sense of identity etc, it also has additional features that makes it different from most - not all - movements that came before. One of them I want to bring to surface and make salient in everyone's minds. 


Effective Altruism is an intensional movement, not an extensional movement 

This distinction comes from philosophy of language and psycholinguistics, and goes like this: "two to the power of three" and "the number of planets in the solar system" are intensions, both of which capture the same extension, the number 8.

An intension is the way in which a symbol, a sign, or a gesture captures an object. An extension is the object that it captures in that way.

"The morning star" and "the evening star" are both intensions, it just so happens that, though nobody knew about it when they named them, both ended up being the same thing in the world. Both of them capture the same celestial object, which curiously happens to be the planet Venus! Venus is the extension of "the evening star" and "the morning star".  

So what does it mean to say that Effective Altruism is more like an intension than like an extension? It means that the things which unify the different people, thinkers, researchers and donors that compose the EA movement are ways of reasoning, or methods, or perspectives, but they are not ultimately and fully pre-determined and established states of the world. They are not the object, but the means through which we intend to reach the object and capture it - those who were at the 2014 EA Global (Summit) have seen this exposed for instance in Rob Wiblin's talk when he mentioned different moral philosophies all of which compatible with being an EA, but I want to emphasize this again here, given how many times I've found people asking me something to which this was the explanation again.  

The same intension has a very important property when distinguishing movements, it can refer or point to different things at different times. That is, the extension to which the intension is currently pointing can change. "The number of planets" used to point to the number 9, it now points to 8. Effective Altruism as a practice will also necessarily change over time, because the largest marginal returns on effort and resource usage to do the best thing are not stable, and even if they were stable, we don't have immediate perfect direct access to them. 

Effective Altruist currently refers to some groups of people who are aligned on many dimensions, but Effective Altruism is not prescriptive in the way religious movements are, where the object-level behaviors are already established, or the facts are declared known in advance. The thing that unifies for instance the Catholic church is a series of beliefs about extensions, about the behaviors, objects, saints and deities themselves. When a growth planner plans to make the Catholic movement grow, they need to impart that extension into the convertee's mind. When the racial equality movement wants more people to join their cause, the goal is to change people's behaviors and beliefs at the extensional level; they want people to know that and behave as if racial prejudice was unjustified. I use these two examples to clarify that being an extensional movement doesn't mean actually referring to a thing in the world, the Catholic Saints are not actual deities, whereas racial prejudice in fact is unjustified. One false and one true example.


Why does being an intensional movement means a different reference class for EA?

1) It means there is a much more nuanced border between who is an EA or not. 

2) It means EAs will form a gradient of level of EA-ness, as opposed to a binary clustering. Whereas religious movements will measure how central a member is by how intense a person's commitment to not change their mind, for instance how elated they feel about their true belief, how intense their devotion is, EA will see a person as more EA if they hold more beliefs within a large cluster of methodogical beliefs to be right. 

3) It means that people can be persuaded to be EAs even without agreeing with the current priority agenda, if they believe that the EA intension, will, over time, shift towards a better extension, which they currently believe is more valuable. 

4) It means that it is better to compare the growth of EA and how to go about it with the growth of other intensional movements, such as the advent of peer-review, the general adoption of the scientific method or the propagation of universities. These are movements in a sense of course, but it is a narrower sense with very different properties from movements like feminism or socialism. 

5) A different way to see this is that for extensional movements, if my core movement belief is that a sentence P is true, and you believe ~P, then the only way for you to join my movement is if you start believing P and abandon ~P. Not so for EAs. If we currently believe (let's call this G) that the far future is important and we should try to colonize the galaxy, and you believe ~G, it is perfectly reasonable to envision a day two years from now where you continue to believe ~G and you are now an EA, and I who used to believe G have been persuaded by your argument that present people matter more than future people. I do not lose my EA identity by changing my core beliefs about what matters or what should be done. This is not the case for racial, religious or political movements. It is impossible to not believe there is a God and be a full-fledged Catholic, no matter how elated you are, or how careful the procedure through which you arrived at the conclusion of God's inexistence. If you persuaded all Catholics of God's nonexistence, you would not have changed Catholicism; you would have ended it. 

6) EA is in a narrower reference class than that of movements, and many of the intuitions that work for other movements break for EA. There are however other movements that are also about the way in which you capture what you want, not directly about the state of the world that you want.  These should be taken as much more valuable when trying to take the outside view on the development of EA in the long run. 


Some intensional movement examples for ease of reference class availability

When we think of movements and movement building some salient ones come to mind: feminism, political equality, racial equality, scientology, religious movements and socialism are the most salient in my mind. None of these are intensional. So here is a historical list of intensional ones to give a sense of what that class looks like. These are ones which don't pre-establish the behaviors and world states beforehand, but are open-ended and figure them out as they go. 

1) Peer-review

2) Universities

3) Open source software community

4) Academic philosophy

5) Lesswrong 

6) MIT

7) US Army 

8) Gates Foundation

When in doubt as a heuristic, try to use the P to ~P shift. MIT and the US army could completely re-design their strategic considerations on how to go about being a great university or protecting American lives and they would still be MIT and the US Army. Now the following examples are cases where it isn't clear immediately, so I suggest you try to think if they are intensional or extensional movements before reading on. 

a) Singularitarians

b) Transhumanists

c) Longevity alliance

d) 80,000 Hours.

These were selected because though they are related to the EA community, they are about specific ways for the world to be. The longevity alliance won't advocate shorter lifespans, and transhumanism will not advocate maintaining the status quo of the human condition, and avoiding being better than well. 80,000 Hours is a career adviser. All the members could decide it needs not exist and continue to be EAs, but 80,000 Hours would be dissolved as a consequence. The four examples above are all extensional movements/institutions.

I hope I hear over the course of the next weeks more discussions using examples and drawing valuable conclusions from the narrow set of intensional movements. The EA movement will still change its extension quite a few times until it maybe reaches a more stable desired world state. But no matter how long and how stable, how convergent it ends up being at the end of the day, it will always be open to further scrutiny and change. The outside view on EA should be the outside view on intensional movements, not on all movements. Those who are planning where to direct its movement-aspects have to take that factor into account. I hope from now on everyone will. 


Examples where the distinct reference class of intensional movements makes a difference

Roxanne and Oliver suggested that I give some examples where the emphasis on "intensional movement" makes a difference, and to mention that these are not all the examples, just the intuition pumps to start the engine. 

a) When considering strategically how to interact with members of other movements, there is ample room for collaboration and less need for competition, because frequently one can become an EA without recanting their previous affiliation with some extensional movement. So it changes strategic collaboration considerations. 

b) Intensional movements are more nuanced in how much buy-in individuals need. The transition processes both inwards and outwards towards core community are smoother, and can happen without deep epiphanies, or large cognitive dissonance. 

c) Paul Christiano argues that moral advocacy may turn out to not be the best way to go about building EA, an intensional movement, even though it seems needed for most extensional movements. 

d) Fluid hierarchical positions and merit-based judgement structures are more valuable for intensional than they are for extensional movements. It is better to have one pope until he dies, but several university deans over a decade, preferably not arbitrarily selected. Guru's are frequently attached to the extension of which they are gurus, although it is possible to become a guru-like figure without attaching yourself to any particular extension - e.g. Putnam, Neumann, Feyman. 

e) Intensional structures can be more long-lived without need for cognitive dissonance, they are more epistemically robust to changes in weltanschauung(worldview). Yuval Harari's Sapiens (2014) is a good history book to capture that intuition, it recaptures the whole of history and shows the relative causal unimportance of reactive extensional movements like most religions in the very long run. 

f) Related to the previous point, intensional structures are more dynamic, and permit more action to originate from the inside. Borrowing from Dennett, the intuition here is that intensional movements are not a leash, but a trampoline which enlarges the scope of actions that a group can have.

With these examples I hope the intuition that Effective Altruism is an intensional movement can be steelmanned in your mind into a powerful concept. Sometimes - say, to make hiring decisions - it may well be fine to use movements at large as your reference class, but frequently it is more valuable to think of Effective Altruism as an intensional movement.   



Sorted by Click to highlight new comments since: Today at 2:02 AM

Hm, I'm not convinced that this distinction carves reality at the joints. I notice that your examples of "intensional" movements are mostly either ideas/memes or organizations. I think it's definitely interesting to have a meme level view of EA, or an organization level view. But I'm also inclined to think that the movement level view also has some predictive value.

To try to break your dichotomy more explicitly, does the skeptic movement qualify as intensional or extensional? They seem intensional in the sense that skepticism, in theory, points to a way of looking at the world rather than a predetermined set of conclusions. But in practice, everyone refers to the skeptic movement as a movement and they seem very movement-like. It's even possible that skepticism started out as an intension and it eventually became an extensional movement as it grew, with unfortunate results.

Or take 80K... why is it not an "intension" in the sense that it points to whatever the most effective careers for people to take are?

I think your description of what the skeptic movement possibly is is perfectly accurate, as are the unfortunate results you mention.

Strongly agree. I've said before that I think that EA is in many relevant respects not like a "social movement" but also that even within the class of 'social movements' there's so much diversity that we don't gain much (and possibly only mislead outselves) by drawing comparisons to others within the class- and I think you've captured the point neatly here.

Another way to look at it would be to look again at the formulation that EA is "a philosophy and a social movement." The philosophy can clearly be pursued through very many different 'movements' or means, and it often obscures more than it reveals to talk about 'the movement' as a whole.


I've noticed that what "EA is" seems to vary depending on the audience and, specifically, why it is that the audience is not already on board. For example, if one's objection to EA is that one values local lives over non-local lives, or that effects don't matter (or are trumped by other considerations), then EA is an ethical framework. But many people are on board with the basic ethical precepts but simply don't act in accordance with them. For those people, EA seems to be a support group for rejecting cognitive dissonance.

EA is special, and your core point about thinking things through from first principles rather than relying on what's happened before is strong. But EA is not that special. Other movements are more strictly defined, but no movement is as strictly defined as your characterisation - to the point where 1-3 and 5 break down. 4 doesn't seem to hold because as John Maxwell IV said - your other examples of intensional movements don't seem to be that similarly broad or question-based. But great piece otherwise and helpful in clarifying some of the characteristics of EA.

Your points a-f show the kind of thinking I've been hoping to come across more of.

Relatedly, if an intensional movement is so important for the long run, durable, and easy to move in to - then why are we finding it so hard to come up with good reference examples for intensional movements?

I have heard before that a person who currently holds a very high position within the EA movement predicted that it would fail precisely because of this lower level of connection that intensional movements have versus extensional ones. That person sure is glad now that they were wrong. It is much easier to grip an extensional movement to the ground, so to speak. EA now has traction, as long as we don't push the breaks, let's use it's momentum.

The difficulty of finding intensional movements is related to some cognitive abilities. Science and philosophy took long to evolve though saints, religions and spirits are cheap. I recommend in particular "The prehistory of the mind" by Stephen Mithen to get a grasp of why levels of intentionality are one of the newest characteristics the human mind is able to entertain, and not all human minds are equally good at it. It is connected to levels of intensionality.


I wonder if the 'intensionality' generates a deontological framing. I mean, if Paul donates to AMF because he had malaria as an infant and Mary donates to the same charity because she thinks it is effective, then, Paul is not an EA and Mary is, right?

Yes, and that is a very smart question! You're right.


If Paul pushes someone in front of a trolley because it will kill someone and Mary pushes someone in front of a trolley because it will save two people from getting hit, then Paul is not and EA and Mary is.

Is this a counter example to the 'deontological framing' assertion?


I'm not sure I got your point... do you mean counter example because it proves it is not deontological or because it proves it is not desirable to be deontological? If you look only the consequences paul and mary actions are the same, they kill one to save two. I think it is interesting to think about the practical consequences for the movement of the different approaches. If what matters is only extension it would justify to get adherents no matter what (i don't know, like using strong images, manipulated data...), on the other hand, from an intensional point of view you want adherents that get the point reasonably enough to push it further. Maybe we also need a distinction between adherents that are only interested in knowing good charities to donate to, and those who are willing to push the ideas further


Sorry, I wrote that comment carelessly! I wanted to look into whether the framing is actually deontological.

In your example, they both had the same ends (donating to AMF) and different means (having malaria as a kid or trying to be effective). If I'm correct, you were saying that because it was the means that distinguished the two cases, deontological framing was being used.

But in my example, they both had the same means (pushing someone in front of a trolley) to get to different ends ('saving' one life or killing one life). And in this case, it was the ends that distinguished them. So I was wondering if deontological framing was actually being used.

I suspect that I get what you mean by applying the intensional vs. extensional distinction to movements, and it may be something that I’ve argued only a week ago using different terms, but I’m not entirely sure because my brain might be pattern-matching too eagerly.

Could you give some examples of movements within those classes and why they belong there, so I can better test my understanding? Movements like enlightenment, feminism, animal rights, evidence-based medicine and various other ones that we’re familiar with? Thankies!

You have accidentally read the draft version that was automatically published by a reviewer. The section you asked for was precisely what the reviewers were helping me generate. Glad about the convergence!

Indeed! Turns out what I was arguing was something much more specific. Was it that tricky save button again? I’ve fallen for that once too.

I think I would describe the difference you see rather in quantitative than in qualitative terms. There may be greatly fewer maxims someone has to accept to call themselves EA than there are, e.g., in religions, but I can think of two:

  1. The well-being of other sentient beings is morally relevant.
  2. There are levels of well-being or groups of beings that are greater or smaller than others.

I think if someone rejects either of these, they can’t (and won’t want to) call themselves EA. I know several people who would reject #1 at least in some or most circumstances, and I’ve met people who at least claimed to reject #2 (not sure if after reflection).

This parsimony will hopefully make EA more robust though.