Just noticed this thread (I rarely visit Great Debates) and I thought I’d clarify what I meant.
I do not mean that people in the past or in different cultures are less (or more) intelligent than they are today. I’m assuming that you have the same rough percentage of smart and stupid people you always had (though, obviously, education is probably better nowadays).
What I do mean is that people have different perceptions in different times. For instance, no one in the 1960s thought there was anything wrong with referring to an adult woman as a “girl.” People in the 1950s would think nothing of having a couple of drinks before driving, and chain smoking cigarettes. You were expected when writing a business letter to a woman without knowing if she was married, to address her as “Miss,” because that was more flattering than “Mrs.”
There’s an example I love in the movie Mr. Deeds Goes to Town. Gary Cooper is in his house wearing a dress shirt and pants. Guests arrive. His butler says, “You can’t meet them looking like that,” and insists he put on a dressing gown and ascot.
There was also an Ellery Queen mystery where the murderer went to great lengths to hide the fact that the victim was not wearing a tie – which would have immediately given the killer away. Nowadays a man without a tie wouldn’t have attracted the slightest notice.
It goes further back, of course. Most people imagine how back in Shakespeare’s time, the people spent their evenings in the tavern and then they walked home. But back then, there were few streetlights, and there was a profession of “linkmen” whose job would be to grab a torch and light the way. Note that “Shakespeare in Love” shows no linkmen.
But it’s more than just the obvious examples. Most people nowadays assume that when Shakespeare went home at night, he’d spend the evening watching TV before going to bed. Now, no one is going to admit to that when confronted, but the assumption is that Shakespeare would spend his evening the same way we do until you point out the issues. (Most likely, once he got home, he’d go to bed as soon as it was dark – candles were expensive and didn’t give much light).
The examples are endless. They cut across cultures as well as time, but people are more aware of the differences with a different culture, and not with their own. And what happens is that the assumptions of our day are used to try to interpret actions of another.
This is especially true of things pertaining to sex. People have claimed Lincoln was gay because he shared a bed with another man. But in the 19th century, two men sharing a bed was not an automatic indication of anything sexual going on. Lincoln would never have understood the “that’s not a pillow” joke in Planes, Trains, and Automobiles for instance, since homosexuality was not something people were conscious of (My father, for instance, didn’t know until that Benjamin Britten had fallen deeply in love with him until over 40 years later, despite the fact Britten gave him signs that would have been unmistakable today) .
But the issue is pervasive. Changes in society cause changes in how people think. Everything we see is influenced by our social background, and that background has changed over time. So when we try to interpret what is going on in the past, we have to always be aware of the context and the way the people of the time would look at things, and not come to conclusions because we look at them in a particular way.