‘Impossible’ Logic Puzzle: How Many Liars Can You Tell at a Party?

Imagine you are at a party with 100 people, and those party members are one of two types of people: either truth tellers who always tell the truth, or liars who always lie.

Now, imagine that before going home, some of them shake hands. Then you ask everyone: “How many truthful people did you shake hands with?” One person tells you 99, then they say 98, then 97, 96, 95 … and so on, until 0.