Therein lies the evil. Man is not a thing. A nuclear bomb is neither good nor evil but can be used for either. A man (or a Vulcan) is responsile. Someone like Spock who could comprehend, and could even calculate the odds, had a responsibility to decide.
I know not everyone is a Christian, but Jesus said that he would rather someone be hot or cold than luke warm. Mirror Spock was luke warm - someone who could figure out the right thing to do, but didn't bother until someone pressed him to think.
Man is the ultimate thing.
Out of the ashes and mud of reality, infused with a spiritual essence, man is a thing of mud-pie functionality and utility. In other words, he is utterly and unutterably useless until he makes something significant of himself.
Being a mud-pie, he can shape himself into whatever he chooses to become, because the essence of his endowment is to be a maker, like his Creator.
Even a "self-made man" cannot take all the credit, because God provided the dirt.