For some people, the scientific description of the universe — its incomprehensible age, its improbable fine-tuning, the fact that stars had to die to make the atoms in your body — produces something that functions exactly like awe and exactly like gratitude, without requiring a deity to direct it toward. This is not a second-best spirituality; it may be one of the most honest ones available. Nasreddin would have approved of any path that ends with genuine astonishment — that was always the destination.
Each step builds on the last.