For breaking the natural law, there are natural penalties.  Those who live by knives die by them. Those who betray their friends lose them.  Those who abandon their children never know the sweetness of their kiss.  Those who travel from bed to bed lose the capacity for trust.  Those who torture their consciences are tortured by them in return.  Those who refuse the one in whose image they are made live as strangers to themselves.

This principle of natural consequences is woven into the fabric of our nature.  Not all our defiance can unravel a single stitch.  Some penalties show up within the lifetime of the individual; others may tarry until several generations have persisted in the same wrongdoing.  But the penalties are cumulative, and eventually they can no longer be ignored.

A good example of such further penalties can be found in the consequences of breaking the precept of chastity.  One immediate consequence is injury to the procreative good: one might get pregnant but have nobody to help raise the child.  Another is injury to the unitive good: one misses the chance for that total self-giving which can develop only in a secure and exclusive relationship of true self-giving.  And there are long-term consequences too, among them poverty, because single women must provide for their children by themselves; adolescent violence, because male children grow up without a father’s influence; venereal disease, because formerly rare infections spread rapidly through sexual contact; child abuse, because live-in boyfriends tend to resent their girlfriends’ babies and girlfriends may resent babies that their boyfriends did not father; and abortion, because children are increasingly regarded as a burden rather than a joy.

But the most terrible consequence of doing what we know to be wrong -- the most dreadful penalty of suppressing our moral knowledge -- is that our lies metastasize.  The universe is so tightly constructed that in order to cover up one lie, we must usually tell another, and this applies with just as much force to the lies we tell ourselves as to the lies we tell to other people.  One could imagine a universe so loosely jointed that lies did not require the support of more lies, but the one we live in is not like that. In this one, deception begets deception, and self-deception begets more self-deception; the greater the lie, the greater its metastatic tendency.  This tendency is strongest precisely in the case of the greatest self-deception, pretending not to know that God is real, because there are so many things one must not think of in order not to think of the reality of God.  But it also kicks in when we pretend not to know the foundational principles of natural law.

The downward spiral explains the remark of G. K. Chesterton:  ‘Men may keep a sort of level of good, but no man has ever been able to keep on one level of evil.  That road goes down and down.’  Pursued by the Five Furies of conscience, a man becomes both more wicked and more stupid: more wicked because his behavior becomes worse, more stupid because he tells himself more lies.

Then is the design of conscience defective?  Shouldn’t it drive us up, not down?   Not necessarily.  As Dante found, for some of us the road up goes down for a long time first.  The system of conscience has not broken; it has merely advanced to the next phase.  This is fully compatible with its mission.  After all, the greater purpose of conscience is not to inform us of moral truth, but to motivate us to live by it.  For most of us at some times, for some of us at most times, guilty knowledge is not exhortation enough.  Drastic measures become necessary.  Driving life out of kilter is, so to speak, the exhortation of last resort.  The offender becomes stupider and wickeder—but then he had intended to become stupider and wickeder; that is what obstinacy and denial are all about.  His only hope is to become even stupider and wickeder than he had planned.

If all goes well he may finally be so wretched that he comes “to himself”—or to God.  Apparently, for the chance to soften a heart, the Designer is even willing that it become more rocklike still.  In this life, what has been called ‘the left hand of God’ may be, in reality, the left hand of His mercy.

This is a staggering reflection for those who think of God as a tooth fairy.  Less drastic means of turning a soul around can certainly be imagined.  Probably, though, no less drastic means of turning a soul around are compatible with free will, which seems to be one of His design criteria.  We may find the price too high, because in order to escape the Furies a man may inflict terrible damage on other people.  What this suggests is that the Designer thinks scarcely any price too high to save a soul.  Even souls may be risked to save a soul.  Yet other souls may be risked to save those.

Adapted from What We Can’t Not Know: A Guide