The more similar two options are, the more difficult it is to decide between them, and the less consequential the decision becomes. A rational decider might find herself spending the most time on the least important decisions.

Philosopher Edward Fredkin writes, “The more equally attractive two alternatives seem, the harder it can be to choose between them — no matter that, to the same degree, the choice can only matter less.”

To avoid this, the decider might resolve to apportion her decision-making time by the importance of the decision. But this requires assessing the importance of every decision, which requires evaluating the means she’s using to make those assessments, and so on.

Psychologist Gary Klein writes, “[[I]f I want to optimize, I must also determine the effort it will take me to optimize; however, the subtask of determining this effort will itself take effort, and so forth into the tangle that self-referential activities create.”