McKelvey-Schofield chaos theorem
It states an interesting result in social choice theory - majority rule is unstable in a multidimensional space [1].
In the image, the stickmen refer to potential voters in a democratic process and ${P_1, P_n}$ refer to proposed policies. The euclidean distance between a voter and a policy refers to the voter's inclination towards the policy. In the image, we are assuming that policy $P_1$ is in action, as it is closest to all the voters.
The theorem states that such an arrangement is always unstable, and a malicious "agenda setter" can manipulate the majority vote to reach any policy in the space (like $P_n$) through a sequence of intermediate policies that are closer to the majority but farther from the minority. Only certain unstable equilibria exist where this does not hold.