In a previous post, I discussed how, as a philosopher, one should decide on a research area. I suggested that one method was to work out what are potentially the biggest problems the world faces, work out what the crucial normative consideration are, and then work on those areas. Call that the top-down method: starting with the problem, and working backwards to the actions one should take.

There’s a second method for high impact philosophy, however. Let’s call it the bottom-up method.

Begin by asking ‘which are the biggest decisions that one typically makes in life?’ Then ask: ‘What are the crucial normative considerations that might affect how I should make those decisions?’ Then figure out which of these crucial considerations is most likely to produce an action-relevant outcome given your marginal research time. Then work on that topic! As in my previous post, I’ll go through each step in turn.

1) What are the biggest decisions one typically makes in life?

By ‘biggest decisions’ I mean the decisions that potentially have the greatest positive or negative moral impact. In general, these will be those decisions that involve the greatest amount of resources – where having greater ‘resources’ is just the power to make things happen. So what are the biggest decisions one typically makes in life? The list would certainly include the following:

i. How should I spend my money? Why? Over a lifetime, a high school graduate can expect to earn $1.2million. With a bachelor’s degree, that figure almost doubles to $2.1 million; with a professional degree that number doubles again, to $4.4 million. Considered over a lifetime, almost every person reading this blog is a millionaire.

ii. What career should I choose? Why? A typical lifetime career involves over 80,000 hours of work – that’s more time than we’ll spend on any other activity, except sleeping.

2) What are the crucial normative questions?

There are some questions that have analogues for both (i) and (ii). For instance:

Should I just spend my money/time wherever it has greatest current expected benefit? What are the conditions under which I should:

* Invest my money (e.g. in an index fund) or time (e.g. getting a degree) so that I generate a bigger payoff later?

* Use my money/time to fund/do research into how best to spend my money/time?

* Use my money/time to fund/do research into how best to invest my money/time? There are also subtle concepts that are relevant to both. For example:

* Replaceability: Sometimes, if I don’t work for an organisation, someone else will take my place.

* Similarly, sometimes, if I don’t donate to a charity, then someone else will do so instead, and they’ll fill their room for more funding anyway.

* Compensation: if we remove one doctor from the NHS, then all the other doctors in the NHS will compensate: they’ll stop doing the least important tasks, and do the more important tasks that that one doctor would have done. So the benefit from a marginal (that is, one additional) doctor is far smaller than the average benefit from all doctors.

* Similarly, I should expect that charities do the most cost-effective interventions first, and so the benefit from a marginal dollar will be less than the average benefit from the charity’s expenditure. And there are questions to do with the interaction between these two issues:

* How should I value my time, in monetary terms? Under what conditions should I turn time into money, and vice versa? 3) Which topics would be advanced the most from one’s marginal research time?

Again, a good heuristic is to look at which topics are the least well-studied. The question of ‘giving now vs giving later’ has had only one academic article written about it: interestingly, people tend to find the idea that one should save and give later on, even though we’re perfectly happy with the idea that one should invest time in oneself (e.g. by getting a degree) in order to have greater influence later on, and we’re perfectly happy with the idea that, for self-interested reasons, one should save one’s money now, in order to consume more later on. The question of how much we should discount future time and money has been extensively discussed by economists; but not, to my knowledge, in the condition where one’s principal aim is to benefit others (rather than oneself). I don’t know of any in-depth philosophical discussions of replaceability or compensation effects.

So, though the top-down approach has had very little attention within philosophy, the bottom up approach, to my knowledge, has had basically none. This is remarkable, given the ubiquity and importance of the questions. One possible explanation is practical ethics’ obsession with developments in biomedical science; another might be that so many of the issues often blur with economics, so it’s difficult for non-specialists to contribute. But, finally, it’s worth considering that ethical scrutiny of career choice and our spending habits is radical, in terms of its potential impact on our lives, in a way that discussions of the wrongness of stealing or of cloning typically aren't. And it can be difficult to write on issues that can so greatly affect how one ought to spend one’s time (especially when the conclusion might be that one should stop being a philosopher).