Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

The Joke

A character calculates the probability that their individual vote will decide an election and concludes it's essentially zero, so voting is irrational. Another character points out that if everyone reasons this way, democracy collapses — to which the first character responds that this is irrelevant because they're making an individual decision, not a collective one.

Both are right, which is the problem.

The Humor

The comic illustrates a genuine paradox in rational choice theory: the "paradox of voting." For any individual, the expected benefit of voting (tiny probability of being decisive times the value of the preferred outcome) is less than the cost (time, effort). Yet democracy requires widespread participation to function. The joke is that both the individual-rational case for not voting and the collective-rational case for voting are valid, and they contradict each other.

Context

The paradox of voting has been studied extensively in political science and economics. Various resolutions have been proposed: civic duty, expressive voting (voting to express identity rather than influence outcomes), or rule-based thinking (following rules that would be good if universally adopted). The comic doesn't resolve the paradox — it just finds it funny.