[infimum]

One of the most eye-opening moments of my CS studies was, when we discussed the Gibbard-Satterthwaite Theorem [1] in a class about Algorithmic Game Theory. I always like to bring it up in discussions about voting. In brief it states that every voting system is either 1. dictatorial (only 1 vote really counts) 2. limiting the number of outcomes to 2 3. is not strategy-proof (you have to vote tactically, for example ranking your favourite lower to achieve a better result)basically people have to 'game' the system to get what they want)

It would be interesting to know how different proposed system tackle this. [Iirc one of the more reasonable approaches seemed to be relaxing No. 3 to make strategic voting computationally hard].

[1] https://en.wikipedia.org/wiki/Gibbard%E2%80%93Satterthwaite_...