Think about this one: the doctor can't lose!
For the viewer, the narrative element in the "amnesia" cartoon consists of imagining the future scenarios in which the patient fails to collect on the doctor's offer.
Part of the humor here is that there exists an office for I. Bright the optimist. All of us could probably use a session with Bright -- though if his advice to the man who has just left proves wrong, the "patient" will have to visit a real eye (not "I") specialist.
Virtue-signaling as a sales ploy:
There are at least five virtue signals in the salesman's offer.
The logic of governmental mandates:
Imagine the airflight on which every passenger carries a gun. What could possibly go wrong?
A spoof of the fears about the escalation of destructive weapons in war:
Imagine the narrative sequence in which the brave charges the enemy line with his super-weapon!
No doubt that he doesn't follow directions, the medicine will prove ineffective:
Maybe if the patient could learn to sleepwalk to the medicine counter...
There are a few coins at his feet...
At least some passersby were moved to contribute. I would.