The memento mori — the reminder of death — appears in every serious wisdom tradition: the skull on the Stoic's desk, the Sufi's surrender of the nafs, the Buddhist's meditation on the charnel ground, the Christian's Ash Wednesday. What they share is the conviction that remembering you will die is not morbid but freeing — that the person who faces this truth lives more honestly than the one who manages it away.
Each step builds on the last.