Whether you should do a PhD doesn’t depend much on timelines.

I wrote this as an answer to a question which I think has now been deleted, so I copied it to my shortform in order to be able to link it in future, and found myself linking to it often enough that it seemed worth making a top-level post, in particular because if there are important counterarguments I haven’t considered I’d like to come across them sooner rather than later! I’d usually put more thought into editing a top-level post, but the realistic options here were not post it at all, or post it without editing.

Epistemic status: I’ve thought about both how people should thinking about PhDs and how people should think about timelines a fair bit, both in my own time and in my role as an advisor at 80k, but I wrote this fairly quickly. I’m sharing my take on this rather than intending to speak on behalf of the whole organisation, though my guess is that the typical view is pretty similar.

BLUF:

  • Whether to do a PhD is a decision which depends heavily enough on personal fit that I expect thinking about how well you in particular are suited to a particular PhD to be much more useful than thinking about the effects of timelines estimates on that decision.

  • Don’t pay too much attention to median timelines estimates. There’s a lot of uncertainty, and finding the right path for you can easily make a bigger difference than matching the path to the median timeline.

Going into a bit more detail—I think there are a couple of aspects to this question, which I’m going to try to (imperfectly) split up:

  • How should you respond to timelines estimates when planning your career?

  • How should you think about PhDs if you are confident timelines are very short?

In terms of how to think about timelines in general, the main advice I’d give is to try to avoid the mistake of interpreting median estimates as single points. Taking this metaculus question as an example, which has a median of July 2027, that doesn’t mean the community predicts that AGI will arrive then! The median just indicates the date by which the community thinks there’s a 50% chance the question will have resolved. To get more precise about this, we can tell from the graph that the community estimates:

  • Only a 7% chance that AGI is developed in the year 2027

  • A 25% chance that AGI will be developed before August of next year.

  • An 11% chance that AGI will not be developed before 2050

  • A 9% chance that the question has already resolved.

  • A 41% chance that AGI will be developed after January 2029 (6 years from the time of writing).

Taking these estimates literally, and additionally assuming that any work that happens post this question resolving is totally useless (which seems very unlikely), you might then conclude that delaying your career by 6 years would cause it to have 4191 = 45% of the value. If that’s the case, if the delay increased the impact you could have by a bit more than a factor of 2, the delay would be worth it.

Having done all of that work (and glossed over a bunch of subtlety in the last comment for brevity), I now want to say that you shouldn’t take the metaculus estimates at face value though. The reason is that (as I’m sure you’ve noticed, and as you’ve seen in the comments) they just aren’t going to be that reliable for this kind of question. Nothing is—this kind of prediction is really hard.

The net effect of this increased uncertainty should be (I claim) to flatten the probability distribution you are working with. This basically means it makes even less sense than you’d think from looking at the distribution to plan for AGI as if timelines are point estimates.


Ok, but what does this mean for PhDs?

Before I say anything about how a PhD decision interacts with timelines, it seems worth mentioning that the decision whether to do a PhD is complicated and highly dependent on the individual who’s considering it and the specific situation they are in. Not only that, I think it depends on a lot of specifics about the PhD. A quick babble of things that can vary a lot (and that not everyone will have the same preferences about):

  • How much oversight/​direction your supervisor provides.

  • How supportive the supervisor is.

  • How many other people are in the research group and how closely they work together.

  • How many classes you’ll have to take and what they will consist of.

  • A bunch of other stuff.

  • Whether the job you want to be doing afterwards requires/​benefits from a PhD.

When you then start thinking about how timelines affect things, it’s worth noting that a model which says ‘PhD students are students, so they are learning and not doing any work, doing a PhD is therefore an n-year delay in your career where n is the number of years it takes’ is badly wrong. I think it usually makes sense to think of a PhD as more like an entry-level graduate researcher job than ‘n more years of school’, though often the first year or two of a US-style PhD will involve taking classes, and look quite a lot like ‘more school’, so “it’s just a job” is also an imperfect model. As a couple of examples of research output during a PhD, Alex Turner’s thesis seems like it should count for more than nothing, as does Collin Burns’s recent paper (did you know he was only in the second year of his PhD)!

The second thing to note is that some career paths require a PhD, and other paths come very close to requiring it. For these paths, choosing to go into work sooner isn’t giving you a 6 year speedup on the same career track—you’re just taking a different path. Often, the first couple of years on that path will involve a lot learning the basics and getting up to speed, certainly compared to 6 years in, which again pushes in the direction of the difference that timelines makes being smaller than it first seems. Importantly though, the difference between the paths might be quite big, and point in either direction. Choosing a different path to the PhD will often be the correct decision for reasons that have nothing to do with timelines.

Having said that, there are some things that are worth bearing in mind:

  • Flatter distributions might also put more weight on even sooner timelines as well, and to the extent that you are waiting/​delaying this clearly does have a downside.

  • Shorter timelines are probably correlated with ‘something like current state of the art (SoTA) scales to AGI’, and it’s harder to work on SoTA models in academia compared to in industry.

  • Whether you’ll be able to work on something relevant to alignment isn’t guaranteed (I’m not saying here that people should never do PhDs for ‘pure’ skillbuilding purposes, but I do think that option looks worse with very short timelines).

  • Many paths don’t require a PhD, so doing a PhD before checking whether you can go straight in does look much more straightforwardly like a mistake.

  • Many people shouldn’t do a PhD regardless of timelines. PhDs can be extremely challenging, emotionally as well as intellectually. Personal fit is important for many paths, but I suspect it’s much more important for deciding whether to do a PhD than on average.