"Where could I have got it? By reason could I have arrived at knowing that I must love my neighbor and not oppress him? I was told that in my childhood, and I believed it gladly, for they told me what was already in my soul.

But who discovered it? Not reason.

Reason discovered the struggle for existence, and the law that requires us to oppress all who hinder the satisfaction of our desires.

That is the deduction of reason.

But loving one's neighbor reason could never discover, because it's irrational.