If we avoid the overloaded term "blackmail" and talk of threats vs. trade, Angela is threatening you whereas Julia is offering a trade. I agree that this example shows that "makes you suffer" is not the distinguishing element. It's also interesting that you may not now if the situation is threat or trade (you may not know whether the mistress wants to tell your wife anyway).
I'm not sure how threats and trade are a real dichotomy rather than two fuzzy categories. Suppose I buy food. That's basic trade. But at the same time a monopoly could raise the price of food a lot, and I would still have to buy it, and now it is the threat of starvation.
I can go fancy(N), and say, I won't pay more than X for food, I would rather starve to death and then they get no more of my money, and if I can make it credible, and if the monopoly reasons in fancy(N-1) manner, they won't raise the price above X because I won't pay, but if monopoly reaso...
From the last thread:
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