system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel] Would Tony or Steve be the heroes/men we know them to be if Yinsen and Dr Erskine survived? Or are their paths as heroes *fixed* on these two figures having to die in the process of Iron Man and Captain America being born?

Is the biggest part of their involvement due to the sacrifice/assassination to inspire passion and avenging within the two, or the philosophy they preached to them before they had their hero origins? I'm wondering if they still would have become heroes if their mentor figures survived to guide them after the fact, or if the premature death at the hands of the enemy is a fundamental aspect of making them into heroes.
gpt
I imagine Tony would have still been horrified to know how his weapons were being used and want to change Stark Industries and become Iron Man. He’d also no doubt remain in contact with Yinsen if the latter survived, ensuring he’d have a mentor who would encourage him to use his newfound lease on life for the better. 

Erskine wouldn’t have chosen Steve to receive the serum if he didn’t think he would be able to stay a good man throughout the tests of time. Captain America may not have gone through the same trials to be born, but Erskine and Steve would work together no matter what to ensure good was being done.