Amid the growing calls for President Biden to drop out of the election, there’s another ongoing debate: Should there be an age cap for presidential candidates? We talked to Rose McDermott, a political scientist at Brown University. Here’s what she had to say… What are the pros of having an age limit for presidential candidates? There’s a minimum age: You have to be [at least] 35 to be president. Part of the reason the founders of the Constitution didn’t have an upper age limit is that nobody lived long [enough] to have to worry about somebody outliving their performance. But clearly, the founders were concerned about characteristics associated with age or they wouldn’t have had a minimum age … There are good reasons to be concerned about the age of leaders because there are certain illnesses that are much more likely [to develop] as you get older. Some of them are things like cancer, but a lot of them are also things that are concerning for decision-making, like Alzheimer’s. I think the idea is not just whether or not you want an age limit or a series of tests that are required for somebody to pass … the idea is to protect the nation against the consequences that come with particularly devastating neurological diseases. Is there any benefit to not having an age cap? As people get older, they do increase in wisdom. It’s what you call crystallized knowledge, which is the ability to synthesize the information that you acquire across the course of a lifetime and apply it in new situations. There can be benefits to that. But that happens only when somebody isn’t also having an illness at the same time. That’s why something like cognitive tests might be useful. Should there be a constitutional age cap for presidents? Yes, I’ve argued that for a while … I think that the percentage of the population now that’s over 65 is … less than 20%. The problem is that once somebody gets above a certain age, they are no longer representative of the majority of the population, which is a lot younger. Maybe at certain times, like in World War II, that didn’t matter so much. But now when you have pressing concerns — like climate change and AI — that are so tied to novel technologies and future problems, it’s just really hard to envision that somebody who’s generationally not representative of the majority of the population is the best choice … My one moment of hesitation [on the age cap] is that you can lose somebody who can be really valuable. PS: This interview has been edited for length and clarity.