Why did the ancients say that man can conquer nature, and then he said that destiny cannot be violated?

Thinking that victory is in the palm is related to the mentality under adversity. I think all unfairness is given by God, so as long as we persist, we can overcome these adversities. Destiny cannot be violated, that is to say, some things have their own natural operation rules, so don't destroy them artificially. If you do it, you will go against the sky and lose. The former is to give you a motivation to persist in adversity. The latter tells you that everything follows the laws of nature and don't do stupid things in wishful thinking.