I am about a third of the way through a biography of Benjamin Franklin, and an odd thought has struck me. No matter what age Franklin was when he was doing what the author describes, I always picture him as a wizened old man.

The picture stuck in my head is the famous portrait of Franklin from the $100 bill. The portrait painted by Siffred Duplessis in 1778, when Franklin was around 72 years old. But so many of Franklin’s accomplishments and famous feats happened long before this. For example, the famous experiment involving the kite happened in 1752, when Franklin would have been in his mid 40s. He probably would not have been greying. Probably would not have been so portly. Probably would not have been so tired.

People like Franklin should be remembered as people who lived incredible lives, their whole lives. But it is very hard to picture them as anything but their grandest and most celebrated selves.