This is a guest post by University of Connecticut political scientist Stephen Benedict Dyson.

Surveying reaction to the passing of Nelson Mandela, Joshua Tucker ably states the view of many political and social scientists on the importance of leaders: they matter less than is commonly assumed. Compared to journalists, policymakers, historians, and citizens, political scientists attribute less importance to individual political figures and more to broader causes, such as the economic and social factors Tucker cites as driving democratization in states like South Africa.

Why do political scientists place less emphasis on the importance of individual leaders? One reason is that science means moving from studying specific phenomena to developing general explanations. Why South Africa democratized leads to the question of why countries democratize. The more instances of democratization that there are to explain, the less the vivid details of each case – such as a monumental leader – seem to matter. Explanations of many events cannot logically rest on the idiosyncrasies of one event.

The distinctive features of a leader – Evan Lieberman identified Mandela’s remarkable self-restraint – are also harder to measure than factors like the economy.  Instead, political scientists are more likely to make assumptions about leaders’ motivations rather than measure them.  As Lieberman wrote, “People in my line of work, studying politics, tend to make rather dismal assumptions about political leaders: that they are selfish and strive only to stay in power and enrich themselves and those around them.”  (Of course, such assumptions are not unique to political science.)  These assumptions are part of the effort to build general explanations. If leaders behave in relatively uniform ways and seem to have the same core motivations, they can be incorporated into these explanations.

But this way of viewing leaders should give us pause.  As Henry Kissinger once mused, “As a professor, I tended to think of history as run by impersonal forces. But when you see it in practice, you see the difference personalities make.” Fred I. Greenstein, a foundational figure in the modern study of political leaders, believes that many of the objections political scientists raise about the endeavor are at best only partially correct. The issue, for Greenstein, is not whether leaders matter, but under what circumstances they matter. Sometimes, leaders really don’t make a difference. When political decisions are routine, leaders act as interchangeable functionaries. At the other end of the spectrum of urgency – when the “room is on fire” to use Robert Jervis’s phrase – the obvious course of action is to run screaming, and individual idiosyncrasies again won’t make much of a difference.

Yet there is a vast terrain between the routine and the room on fire. Many situations offer a range of reasonable options and thus some capacity for entrepreneurial action. In these ambiguous or malleable environments, different leaders will often make different decisions. We can’t provide conclusive evidence of this, since we cannot re-run the same situation with different leaders and see if the outcome changes. But we can think about the impact of leaders in reasonably disciplined ways, wondering, to use two examples much on our minds in recent weeks, how Richard Nixon would have fared in the Cuban Missile Crisis had a small number of votes gone the other way in the 1960 presidential election, and how John F. Kennedy would have managed America’s involvement in Vietnam had the trajectory of his assassin’s bullet differed but a few inches.

Tucker draws our attention to the dangers of the “great leader” view of politics: it promotes apathy and resignation as we wait for superheroes to appear and fix all of our problems. Yet there are also dangers in minimizing the role of leaders, and they go beyond missing important causes of major events, although this is a clear risk. In the explanations of historians, the reporting of journalists, and the political decisions of citizens, leaders often play the role of personifying abstract trends, ideas, and forces, and offering a human connection between politics and life. People learn, understand, and are motivated to take action by compelling narratives, and compelling narratives involve individual human beings. A worthy goal of science is to provide systematic, rigorous knowledge about issues of social importance. But science should also engage with the moral and empathetic possibilities that come from taking leaders seriously.