How does he know that we can override genetic behaviors? Sure, we can try, but that doesn't mean that we can override them.
Given that you could view large parts of human culture as semi-successful overrides of instinctual behaviors, I'm not entirely sure what kind of thing your thinking of that might not be possible even in principle. Not feeling the instinctual impulses to begin with as opposed to not acting upon them?
Given that you could view large parts of human culture as semi-successful overrides of instinctual behaviors, I'm not entirely sure what kind of thing your thinking of that might not be possible even in principle. Not feeling the instinctual impulses to begin with as opposed to not acting upon them?