The more "adventurous" an adventure, that is, the more fully it realizes its idea, the more "dreamlike" it becomes in our memory. It often moves so far away from the center of the ego and the course of life which the ego guides and organizes that we may think of it as something experienced by another person. How far outside that course it lies, how alien it has become to that course, is expressed precisely by the fact that we might well feel that we could appropriately assign to the adventure a subject other than the ego.

QUESTION: What distinguishes an adventure that remains ego-anchored from one that becomes alien? Is this threshold measurable or purely subjective?

Georg Simmel, on individuality and social…, loc. 465