Running has a logic that is simple rational and gets you where you want to go.
It is possible to apply a rational logic to what can appear to be an irrational activity. The logic of running doesn’t require irrationality because the activity of ultra-running can appear irrational.
In any event all it takes to change ultra-running to a rational activity is to extend the context in which to judge it far enough. That which in normal terms looks irrational, becomes, on a grander stage, rational.
Sometimes when running you have to remind yourself of this. Sometimes deep in training you have to take a deep breath and remind yourself of this. Sometimes deep in a long run, you should forget all this and focus on running.