There's an discontinuous difference between mutual knowledge and common knowledge.

  • There's an discontinuous difference between mutual knowledge and common knowledge.
    • Mutual knowledge is knowledge that everyone individually has.
    • Common knowledge is knowledge that everyone and individually has… and everyone knows everyone knows.
    • In the mutual state, you don't know if an action you take will be supported by others.
      • But in the common state, you know it will be.
    • Before it's common knowledge, spontaneous coordination is hard.
      • After it's common knowledge, spontaneous coordination becomes the default.
    • The emperor having no clothes is an example.
    • Bubbles are another example.
      • Even if everyone privately thinks we're in a bubble, if it's not yet common knowledge, then if you short the bubble you'll get wiped out.