Edit: Yes, I misread. The numbers represent payoff, not number of years in prison, which is what my brain tends to auto-fill in for numbers when encountering the prisoner’s dilemma. I followed the rest, and your bit describing the common-knowledge generating feature of religion lit the bulb over my head, I enjoyed that part! It really threw into sharp relief how and why religion has been so strong and effective for thousands of years.
A couple nitpicks of the Prisoner’s Dilemma illustrated matrix (assuming C refers to being silent, and D to snitching):
C/C, at 3⁄3, seems worse for both than D/D at 1⁄1, when it’s stated that both cooperating is better than both defecting.
In the respective C/D and D/C boxes (assuming that the format is Anne/Bob), the numbers seem backward to me: if Anne cooperates and Bob defects, then Bob should get off free (4/0) -- but the matrix has that outcome labelled as (0/4).
I stared at it for a few minutes, and I’ll feel silly just for a bit if it turns out that I just kept misreading it, but better that than continuing to be confused, so let me know if I just read it wrong!
The voting example is good — contingent on the voting system being plurality/FPTP, as used in most of the English-speaking world. In better voting methods, no coordination, thus no common knowledge, would be needed.
You’re welcome (encouraged!) to reply to this comment with disagreements with or nitpicks of the examples and theory in the post.
Edit: Yes, I misread. The numbers represent payoff, not number of years in prison, which is what my brain tends to auto-fill in for numbers when encountering the prisoner’s dilemma. I followed the rest, and your bit describing the common-knowledge generating feature of religion lit the bulb over my head, I enjoyed that part! It really threw into sharp relief how and why religion has been so strong and effective for thousands of years.
The voting example is good — contingent on the voting system being plurality/FPTP, as used in most of the English-speaking world. In better voting methods, no coordination, thus no common knowledge, would be needed.