What do you mean, "If one of us dies first, I think I will move to Paris"? I saw it in the chapter of self-help bias in psychology ~

This is a subtle and short joke, but it is not difficult to find that there is a selfish tendency in human instinct. This husband subconsciously hopes that he will die later than his wife. But for the sake of civility and etiquette, he wants to implicitly say, "whoever dies first and survives will go to Paris to buy a house."