“A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”
As the above quote by Max Planck suggests, science is a very human affair. While, in an idealized form, the scientific process is a very useful tool for discovering truth, the reality of using the process in the world can be substantially messier. One of the primary culprits of this messiness is that being a good scientist per se – as defined by one who rigorously and consistently applies the scientific method – is not necessarily any indication that one is particularly bright or worthy of social esteem. It is perfectly possible to apply the scientific method to the testing of any number of inane or incorrect hypotheses. Instead, social status (and its associated rewards) tends to be provided to people who discover something that is novel, interesting, and true. Well, sort of; the discovery itself need not be exactly true as much as people need to perceive the idea as being true. So long as people perceive my ideas to be true, I can reap those social benefits; I can even do so if my big idea was actually quite wrong.
Sure; it looks plenty bright, but it’s mostly just full of hot air
Just as there are benefits to being known as the person with the big idea, there are also benefits to being friends with the person with the big idea, as access to those social (and material) resources tends to diffuse to the academic superstar’s close associates. Importantly, these benefits can still flow to those associates even if they lack the same skill set that made the superstar famous. To put this all into a simple example, getting a professor position at Harvard likely carries social and material benefits to the professor; those who study under the professor and get a degree from Harvard can also benefit by riding the coattails of the professor, even if they aren’t particularly smart or talented themselves. One possible result of this process is that certain ideas can become entrenched in a field, even if the ideas are not necessarily the best: as the originator of the idea has a vested interest in keeping it the order of the day in his field, and his academic progeny have a similar interest in upholding the originator’s status (as their status depends on his), new ideas may be – formally or informally – barred from entry and resisted, even if they more closely resemble the truth. As Planck quipped, then, science begins to move forward as the old guard die out and can no longer defend their status effectively; not because they relinquish their status in the face of new, contradictory evidence.
With this in mind, I wanted to discuss the findings of one of the most interesting papers I’ve seen in some time. The paper (Azoulay, Fons-Rosen, & Zivin, 2015) examined what happens to a field of research in the life sciences following the untimely death of one of its superstar members. Azoulay et al (2015) began by identifying their sample of approximately 13,000 superstars, 452 of which died prematurely (which, in this case, corresponded to an average age of death at 61). Of those who died, the term “superstar” would certainly describe them well, at least in terms of their output, generating a median authorship on 138 papers, 8,347 citations, and receiving over $16 million in government funding by the time of their death. These superstars were then linked to various subfields in which they published, their collaborators and non-collaborators within those subfields were identified, and a number of other variables that I won’t go into were also collected.
The question of interest, then, is what happens to these fields following the death of a superstar? In terms of the raw number of publications within a subfield, there was a very slight increase following the death of about 2%. That number does not give much of a sense for the interesting things that were happening, however. The first of these things is that the superstar’s collaborators saw a rather steep decline in their research output; a decline of about 40% over time. However, this drop in productivity of the collaborators was more than offset by an 8% increase in output by non-collaborators. This was an effect that remained (though it was somewhat reduced) even when the analysis excluded papers on which the superstar was an author (which makes sense: if one of your authors dies, of course you will produce fewer papers; there was just more to the decline than that). This decline in collaborator output would be consistent with a healthy degree of coattail-riding likely taking place prior to death. Further, there were no hints of these trends prior to the death, suggesting that the death in question was doing the causing when it came to changes in research output.
Figure 2: How much better-off your death made other people
The possible “whys” as to these effects was examined in the rest of the paper. A number of hints as to what is going on follow. First, there is the effect of death on citation counts, with non-collaborators producing more high-impact – but not low-impact – papers after the superstar’s passing. Second, these non-collaborators were producing papers in the very same subfields that the superstar had previously been in. Third, this new work did not appear to be building on the work of the superstar; the non-collaborators tended to cite the superstar less and newer work more. Forth, the newer authors were largely not competitors of the superstar during the time they were alive, opting instead to become active in the field following the death. The picture being painted by the data seems to be one in which the superstars initially dominate publishing within their subfields. While new faces might have some interest in researching these same topics, they fail to enter the field while the superstar is alive, instead providing their new ideas – not those already established – only after a hole has opened in the social fabric of the field. In other words, there might be barriers to entry for newcomers keeping them out, and those barriers relax somewhat following the death of a prominent member.
Accordingly, Azoulay et al (2015) turn their attention to what kinds of barriers might exist. The first barrier they posit is one they call “Goliath’s Shadow”, where newcomers are simply deterred by the prospect of having to challenge existing, high-status figures. Evidence consistent with this prospect was reported: the importance of the superstar – as defined by the fraction of papers in the field produced by them – seemed to have a noticeable effect, with more important figures creating a larger void to fill. By contrast, the involvement of the superstar – as defined by what percentage of their papers were published in a given field – did not seem to have an effect. The more a superstar published (and received grant money), the less room other people seemed to see for themselves.
Two other possible barriers to entry concern the intellectual and social closure of a field: the former refers to the degree that most of the researchers within a field – not just the superstar – agree on what methods to use and what questions to ask; the latter refers to how tightly the researchers within a field work together, coauthoring papers and such. Evidence for both of these came up positive: fields in which the superstar trained many of the researchers in it and fields in which people worked very closely did not show the major effects of superstar death. Finally, a related possibility is that the associates of the superstar might indirectly control access to the field by denying resources to newcomers who might challenge the older set of ideas. In this instance, the authors reported that the deaths of those superstars who had more collaborators on editorial and funding boards tended to have less of an impact, which could be a sign of trouble.
The influence of these superstars on generating barriers to entry, then, were often quite indirect. It’s not that the superstars were preventing newcomers themselves; it is unlikely they had the power to do so, even if they were trying. Instead, these barriers were created indirectly, either through the superstar receiving a healthly portion of the existing funding and publication slots, or through the collaborators of the superstar forming a relatively tight-knit community that could wield influence over what ideas got to see the light of day more effectively.
“We have your ideas. We don’t know who you are, and now no one else will either”
While it’s easy (and sometimes fun) to conjure up a picture of some old professor and their intellectual clique keeping out plucky, young, and insightful prospects with the power of discrimination, it is important to not leap to that conclusion immediately. While the faces and ideas within a field might change following the deaths of important figures, that does not necessarily mean the new ideas are closer to to that all-important, capital-T, Truth that we (sometimes) value. The same social pressures, costs, and benefits that applied to the now-dead old guard apply in turn to the new researchers, and new status within a field will not be reaped by rehashing the ideas of the past, even if they’re correct. Old-but-true ideas might be cast aside for the sake of novelty, just as new-but-false ideas might be promulgated. Regardless of the truth value of these ideas, however, the present data does lend a good deal of credence of the notion that science tends to move one funeral at a time. While truth may eventually win out by a gradual process of erosion, it’s important to always bear in mind that the people doing science are still only human, subject to the same biases and social pressures we all are.
References: Azoulay, P., Fons-Rosen, C., & Zivin, J. (2015). Does science advance one funeral at a time? The National Bureau of Economic Research, DOI: 10.3386/w21788