Lord, what fools these mortals be! A Midsummer Night's Dream 

That which comes after ever conforms to that which has gone before. Book IV

He who is a philosopher or lover of learning, and is entirely pure at departing, is alone permitted to reach the gods. And this is the reason, Simmias and Cebes, why the true votaries of philosophy abstain from all fleshly lusts, and endure and refuse to give themselves up to them—not because they fear poverty or ruin of their families, like the lovers of money, and the world in general; nor like the lovers of power and honor, because they dread the dishonor or disgrace of evil deeds. The Trials Of Socrates

Good habits can make rational sense, but if they conflict with your identity, you will fail to put them into action. Atomic Habits