Do I dare? Time to turn back and descend the stair...

And indeed there will be time
To wonder, “Do I dare?” and, “Do I dare?”
Time to turn back and descend the stair,
With a bald spot in the middle of my hair— 40
[They will say: “How his hair is growing thin!”]
My morning coat, my collar mounting firmly to the chin,
My necktie rich and modest, but asserted by a simple pin—
[They will say: “But how his arms and legs are thin!”]
Do I dare 45
Disturb the universe?
In a minute there is time
For decisions and revisions which a minute will reverse.