George Washington always refers to George Washington. The pronoun he, on the other hand, can refer to George Washington, Thomas Jefferson, John Adams, or anyone else who is male (not just presidents). So, unlike proper names which have the same meaning regardless of context, pronouns have almost no meaning without context.
Just saying that we figure out who he and she refer to based on context begs the question of how we do it. What aspects of context matter? The fact that today is Tuesday? Whether it is sunny or rainy? (This isn't a straw man -- both of these things can matter in the right circumstance; I leave it to the reader as an exercise to come up with examples.)
In one of our newest experiments, we took sentences with pronouns and systematically obscured aspects of the context to see if people could still figure out who the pronoun refers to. If they can, then that aspect of the context didn't matter. Play Pronoun Sleuth by clicking here.
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