system
Given the following post, respond as if you're commenting on Reddit:
human
What does Sartre mean when he states that 'In fashioning myself I fashion man'?

Sartre's theory that existentialism is a humanism includes the idea that our actions account for actions of all mankind. He says 'I am thus responsible for myself and for all men'
I understood this to be an extension of Kant's categorical imperative whereby one's actions are only morally acceptable if they can be acted by everyone and not cause a problem. 'act in accordance with the maxims of a member giving universal laws for a merely possible kingdom of ends'.

Am I miss-understanding what Sartre meant?
gpt
Not really mis-understanding, though he's exploring something a little bit different from Kant. Sartre is saying that the actions you choose are ultimately the actions you believe anyone ought to choose, and that in this way all of your choices reflect your ideal of a person. You are creating your own ideal of a person in yourself, through your actions.