Summary
Making it possible for people to deliberately fall in love seems like a high priority, competitive with good short- and medium-term causes such as malaria prevention and anti-aging. However there is little serious work on it. While this prevents casual donors from being able to do anything about it, it also suggests major opportunities for well-placed researchers, grantmakers, and business entrepreneurs. Both replications and generalizations of the tiny body of existing work, and ambitious science to figure out new paradigms and prospects, could be big steps forward.
If you want the shortest possible pitch to memorize and give to funders/researchers, I would simplify it to this: attempt to replicate a 1997 experimental finding which suggested that you can make people fall in love with a questionnaire and eye contact.
The problem and the type of potential solution
Not everyone falls in love, and when then they do, it often happens with the wrong time, place or person. What I have in mind, ideally, is a relatively quick and cheap activity, using behavioral, psychological and/or pharmaceutical techniques, that two people who have already matched for general compatibility (e.g. with a kind of dating service) can take in order to induce a mutual limerence-like state that can naturally turn into a stable long-run relationship.
Previous inquiry and next steps
Aron et al (1997) devised and tested a questionnaire technique along with sustained eye contact, which induced temporary interpersonal closeness. Their goal was not to establish long-term relationships, but to mimic relationship status for experimental purposes. Still, it could be incidentally useful for pursuing love, as well as a foundation for more serious efforts. Apparently two of the experimental participants later got married. Writer Mandy Len Catron also experienced and explored the idea in a popular article and a book memoir, suggesting that it worked for her too. (I haven’t read the book.)
It seems to me that the cheapest/easiest next step is more longer-term followup inquiry with the participants of Aron et al. An obvious further step, given the replication crisis in psychology, is to attempt a direct replication of the experiment. And it would perhaps be equally important to repeat the study with different experimental designs and cultural contexts in order to address the generalizability crisis. Long-term followup surveys should also be conducted. After all this is done, we may be able to say with confidence that the questionnaire technique works (or not).
Quintard et al (2020) tested a technique of synchronous Interpersonal Multisensory Stimulation (IMS) on heterosexual women. They were able to induce general feelings of liking and being attracted to others, but found no significant effect on romantic attraction in particular. The authors write that the effects of their technique may still be an important part of inducing romantic attraction and that their construct validity is uncertain, and call for further investigation. Further testing of this might be a good next step.
There is also relevant work on inducing attraction via arousal. A variety of studies (table taken from Allen et al, 1989) have shown that people can feel greater feelings of romantic or sexual attraction when put in a situation of arousal from other things like anxiety or exercise. Allen et al replicated and confirmed two of the previous experiments (though it was not a direct replication attempt, just a follow-up study). However there are some limitations. There are differing results, between Allen et al and White and Kight (1984), on whether this still works when subjects are more aware of the source of their arousal. Furthermore, it’s not clear if the results will extend to subjects who are not just introspective of their arousal, but fully aware that they are receiving an arousal-attraction experimental effect towards another person, which is necessary for real-world use of the technique. Also, many of these studies just look at men attracted to women, and they should be generalized. Finally, it’s not clear if there are any effects past the initial state of arousal.
These three approaches – questionnaire/eye contact, synchronous IMS, and arousal – might be done in combination with each other for a more potent effect. And fully new techniques could be devised.
Quick comparison with solving aging
Solving love and solving aging seem like roughly similar cause areas in their basic profile, so they make a good pair for comparison. But I don’t know enough about the prospects for solving love to do a good cost-effectiveness calculation, so I have to rely on the importance-neglectedness-tractability framework.
Tractability
I have little sense of the (in)tractability of either one. Aging seems to be an issue that should in principle be solvable, but could well turn out to be a beast like cancer in practice. Meanwhile it’s very unclear to what extent love can be manipulated. There are many factors affecting it, including individuals’ needs and wants.
The promising early results of Aron et al in an apparently cheap and simple experiment suggest high tractability of initial research steps. The potential next steps discussed above certainly seem easier than pursuing major medical science on aging. It is possible that we already have a good enough method to start inducing attraction thanks to Aron et al, though it seems clear that more research is a better thing to focus on at this stage.
One should also consider the issue of whether potential therapies in either cause area are easily testable. If therapies are easy to test, that increases the priority of developing some, because we can expect more proven results. But I don’t see much reason to think that pro-love therapies will be easier or harder to test when compared to anti-aging therapies.
Neglectedness
Aging is usually considered to not get the appropriate amount of attention from medical science that is warranted by its major importance. But it still seems to be less neglected than love in terms of medical and pharmaceutical research. Romantic pairing is already served by a major industry of dating services, which complicates the picture, but this doesn’t extend to research on how to deliberately induce it. It seems that love is more neglected.
Importance
The nature of this comparison may depend on issues in population ethics. Here I will look at the impacts under a totalist viewpoint, as I’ve found it to be (a) the one most supported by strong arguments, (b) the one seemingly endorsed by a majority of Effective Altruists, (c) the one seemingly endorsed by a plurality of philosophers, excepting those with vague/indeterminate views, (d) the simplest one to evaluate, and (e) consistent with standard ways of evaluating the benefits of solving aging.
I don’t think that differences in value theory matter much here: I can’t think of value theories which would uniquely value or devalue issues of love relative to issues of morbidity and mortality. There are probably some traditionalist views which say that aging doesn’t matter because it’s part of the human condition or whatever, but I’m happy to ignore those.
Scope of direct impact
Aging hurts the entire population, so everyone could benefit from anti-aging therapies. Those who die from other causes such as infectious diseases, accidents and suicides will not get the benefit of longevity, but in the meantime they could still be healthier and happier thanks to rejuvenation therapy.
Some people find mutually requited love naturally anyway, but they could get it sooner, and perhaps with partners who are better on pragmatic grounds.
There is also a possibility that people will decline to adopt the technology. People currently have a variety of spiritual and philosophical reasons to object to either kind of treatment, not to mention plain aversion or disgust. However, it’s wholly unclear how these attitudes will actually develop and affect society once effective interventions are offered for adoption.
Overall, nearly everyone will be affected by these interventions, so scope doesn’t give much reason to favor either one.
Direct change in average quality of life
Assuming that population size remains the same after either intervention, we are comparing one very long life (centuries or perhaps longer) with multiple people who are born and dying with better romantic experiences. This is difficult.
Senior people seem to be happier than younger adults, but it’s difficult to say what this implies for the happiness of people who live a long time without aging. Optimistically speaking, people could get the best of both worlds – benefits from both youthful physiology and life experience.
Ending aging would seem obviously beneficial for improving sex life. There isn’t a clear relationship between aging and sexual satisfaction, at least from younger to older adults, but solving aging may allow people to retain youthful virility and attractiveness while also acquiring the “skills and strategies” associated with age.
One impact of switching to an aging-free society is that people would spend much less of their lives as children, proportionally speaking. I can’t find good evidence on the quality of life of children compared to adults; it is not an easy comparison. My current opinion is that childhood is probably worse on average. Children seem to suffer from high sensitivity to frequent physical and mental traumas, but – despite the vague and dubious nostalgic notion of ‘innocence’ – don’t seem to experience comparable experiential highs. Much of the perceived value of childhood comes from their freedom and independence, rather than being very young per se. If we solved aging, we could spend less resources on raising children, and could then spend those resources on supporting adults in early retirement or longer vacations, so that the general provision of freedom and recreation in society would not decline.
Stopping aging would make the actual experience of dying rare; natural deaths could theoretically be made indefinitely rare or nonexistent. Morbidities associated with aging could be greatly reduced or ended. See this post for details.
On the other hand, inducing love would provide major direct improvements for subjective well-being over a period of decades. Some of the known downsides of love could be mitigated since people would mutually induce it with partners, perhaps selected on the basis of objective compatibility criteria.
It’s not clear which intervention would be more beneficial here. My personal view is that the costs of the aging cycle are less than the value of a hypothetically ideal love life (leaving aside the indirect socioeconomic impacts of these things, to be discussed shortly). I took a small Twitter poll of people’s preferences which had split results, but personal identity issues might have confounded it to provoke pro-longevity responses.
Overall, both interventions would have large direct positive impacts on quality of life, and it’s not clear which is greater.
Impacts on population size
Aging would grow the human population by averting deaths, but it’s not clear if many people will keep having more generations of children as they grow older. Love can grow the human population by creating more stable couples willing and able to raise children. I would guess that solving aging will do more to grow the population.
To be clear, I think a larger population is a good thing in expectation. The current value of population growth is weakly positive, according to the Candidate Scoring System (see the policy position on abortion). However, population growth in the future – after anti-aging or pro-love treatments are developed and widely deployed – seems to have stronger upsides and weaker downsides. It is likely that environmental challenges will be better solved with future technology, the demographic transition will be exacerbated, the population will decline, and inhumane animal farming will decline. Note that even though some environmental challenges (like climate change) will become more dire in the future, excess pollution in the future is still not as bad as excess pollution now, because the pollutants will spend less time damaging the environment.
Overall, this issue provides a weak reason to focus on anti-aging.
Economic impacts
Solving aging would likely be a huge step forward for the economy. The lower rate of population turnover would mean less expenditure on schooling, and the reduction in mortality/morbidity would greatly reduce the burdens of healthcare and social services. People could accumulate greater amounts of skills and experience over longer working careers. See this post for details on the ‘longevity dividend.’
The economic benefits could be rather unevenly distributed if longevity treatments are only affordable to a small part of the population. Permanent social stratification could ensue if rejuvenation therapy remains just expensive enough to be out of reach of poor people over their lifetimes while being continuously affordable to high-productivity people. Within democratic countries, a combination of technological progress, economic growth, government welfare and private charity should head off this potential problem in a reasonably timely manner. In autocracies and between different countries, there is more risk of permanent stratification, but again the most likely scenario is that rejuvenation therapy will proliferate sooner or later, just as with other medical technologies.
Solving romance would not be likely to achieve much economic impact. One study found that students in intense passionate love performed worse at two simple tests of cognitive control. This is one study that has not been tested for replication, and the link with actual economic productivity was not established, so this is only weak evidence. However it seems pretty plausible that being passionately in love reduces your productivity.
Economic benefits are likely, but not proven, to correspond to greater long-run subjective well-being. (See the long-running debate over the Easterlin Paradox.) It is more clear that economic progress will lead to accelerated expansion of humanity with a larger population and extraterrestrial settlement.
Overall, this issue gives a major reason to focus on anti-aging.
Social change
Ending aging would reduce generational turnover. This would inhibit social change.
There are a couple ways to think about this. First, let’s stick with the focus on welfare. Humanity has broadly, though not consistently, moved towards a more inclusive and egalitarian perspective that cares about more beings’ happiness and suffering. We’ve also gotten better at political and social organization. And we can see various contexts where people’s current values, political and social organizations still have plenty of room for improvement through change. This suggests that continuing humanity’s social change is very important. But this is too enthusiastic a position, for not only does generational turnover create impetus for social change, but it also creates some of the problems associated with social stasis. New generations have different values, make new demands and perceive greater unfairness in the current system. Ending aging would therefore reduce the underlying need for social change as well as the actualization of it. Of course, neither would be eliminated; people can still get new ideas and values over time, and social change is often driven by economic changes and scientific progress rather than mere ideas. So overall, accelerated social change seems good for social welfare, but it’s not as important as one would presume from a naïve comparison between the societies of ourselves and our ancestors.
Social change could also be meta-ethically important. Assuming that there is moral truth and humanity converges upon it, we would probably want more social change even if the consequences seem neutral or bad under our current framework. I disagree: there is no moral truth, and if future generations start to care less about global human and animal welfare, we must unequivocally condemn that. For this reason, and for methodological simplicity in this comparison between the two interventions, I’ll ignore this ”moral progress” take on the value of social change – but you may want to keep it in mind.
Meanwhile, it’s not clear what inducing love can do for social change. Maybe it gives people greater connections and understanding of other people’s perspectives, but people tend to pursue partners who are similar to themselves, rather than making connections across sociopolitical divides. Love could inspire people, or something like that.
Overall, this issue provides a weak reason to prefer inducing love.
Cultural capital
Ending aging would mean that people would accumulate more experience and memories. This kind of wisdom could be quite valuable in a variety of social and political contexts. On the other hand, the reduced frequency of new people with new ideas and perspectives might be a serious loss.
Inducing widespread romance might give some kind of cultural or artistic inspiration to people, but probably won’t have much effect. It might distract people in the same way that it can distract them from economic work.
Overall, this issue doesn’t give a clear reason to favor either intervention.
Families
Reducing or ending age-related deaths would greatly reduce the onset of tragedy and grief for friends and families.
Solving aging might cause people to sort into more stable family relationships, because they have more time to figure things out, or it might cause them to jump around and explore more frequently due to increased discomfort at the idea of being stuck to one person for a literal eternity.
Induced love would be more clearly useful for improving family stability, and would thereby reduce the prevalence of children being raised by single or feuding parents. Many troubled couples already make active attempts to stay together for the sake of their children, and they would presumably be enthusiastic early adopters of this kind of therapy (assuming it can help fix a relationship as opposed to starting one).
This issue doesn’t give us much reason to focus on either intervention.
Evolution
Ending aging would slow human evolution. This might actually be good. Or it might be bad.
Inducing romance could shift the trajectory human evolution as partners would likely be selected on more deliberate grounds. But it’s not clear if this will have a major impact.
Overall, this issue doesn’t give a clear reason to favor either intervention.
Interstellar travel
Solving aging could expedite interstellar travel. Realistic manned voyages to the nearest potentially habitable exoplanets or exomoons would likely take 2-5 centuries, according to the Candidate Scoring System (see the section on space exploration). (If you have heard speculations about 60-120 year interstellar voyages, you are probably thinking about missions to Proxima Centauri b, which most likely has deadly radiation and probably lacks a good atmosphere or surface water.) The lack of crew continuity on such an intergenerational mission is commonly regarded as a significant obstacle to interstellar travel, and solving aging could largely avoid this problem.
However, such missions also face risks of social instability and bad mental health. Inducing romance could be very helpful for addressing this problem, though it still (to me) seems like a less useful thing than solving aging.
Regardless, the spaceship could be captained by artificial general intelligence instead. In the extreme case, spaceships could be designed as very small, very fast unmanned von Neumann micro-probes, and humans might be raised de novo. These scenarios seem to be more likely, despite the sci-fi focus on manned missions. So solving aging probably wouldn’t directly expedite interstellar travel.
Also, any manned interstellar colonization mission would probably have to launch well after 2100, which is long enough that perhaps both challenges will be solved anyway. Interstellar colonization will likely require a sort of transhumanism and/or advanced drugs to adapt to harsh environments, which may entail enough general scientific knowledge that we’ll be able to control things like aging and love anyway.
Overall, this issue doesn’t provide much reason to favor either intervention.
Research spinoffs
Rejuvenation therapy has been speculated to be useful for animals as well. The general line of research could also uncover cures for cancer or other diseases in humans.
It is very hard to see how animals could benefit from techniques to induce love in humans. But inducing love might lead the way towards beneficial cognitive treatments for humans in other contexts. It might provide a way to shut down unrequited love or nasty relationship troubles, which could be extremely valuable.
Summary
Solving aging and inducing love have major and similar direct benefits to human quality of life. Solving aging is much better on economic grounds and does more to grow humanity, though it also incurs a cost of inhibiting desirable social progress. The impacts on culture and families are unclear and difficult to judge. Solving aging would slow human evolution, but it’s not clear if this is good or bad. Both lines of research have significant potential for spinoffs.
Overall comparison: love and aging are comparable priorities
Solving aging seems a bit more important. Inducing love appears more neglected. Its tractability also appears favorable at this early stage. Overall, they seem like similarly high priorities.
Corollary: fixing love is competitive with fighting neglected tropical diseases
Aging research is in turn competitive with malaria prevention, which is one of the most effective direct interventions against global poverty and diseases. Thus (by transitivity) inducing love seems comparably valuable to standard antipoverty work, though of course it could still be worse than bigger issues of economic growth.
Options and recommendations for Effective Altruists
There isn’t a ready place for people to donate money to research on inducing love, but if someone was in a position to do serious research or grantmaking or maybe start a kind of business offering social services, I would say that looking at inducing love appears better than marginal research efforts against aging. The research path for this issue looks promising; it is high-risk/high-reward, but at the same time it could be started with straightforward replication and generalization studies as opposed to difficult paradigmatic shifts or true experimental creativity. Of course, more ambitious science could also be very beneficial here.
Those with psychology research skills will have to think more carefully about the whether they should focus on love, on more ordinary mental health, or on animal psychology (with an eye towards improving conditions on farms, or understanding their well-being in the wild).
The prioritization of this cause area may also be aided by a closer look at how much benefit people get from being in love.
Kudos for seriously recommending a novel-to-EA-for-me intervention! It seems there have been a few relatively novel ideas posted recently, it's been quite nice. I think the base rate for these sorts of interventions making it through all the next filters (much more EA consideration, actual implementation) is quite low, and I don't have particular reason to currently believe this is much different than other recommendations. That said, even if there were a 0.1% chance this were cost-effective, the EV of introducing it could be quite high.
As an aside, if we are getting many novel ideas but there are not enough people to fund/implement them, that's good evidence that we should be worrying more about movement growth (& less about cultivating a small cadre of uber-rational people).
The next logical step is to evaluate the novel ideas, though, where a "cadre of uber-rational people" would be quite useful IMHO. In particular, a small group of very good evaluators seems much better than a large group of less epistemically rational evaluators who could be collectively swayed by bad reasoning.