A drive to procreate

Cicero, On Duties, Book I, p.23

For since it is by nature common to all animals that they have a drive to procreate, the first fellowship exists within marriage itself, and the next with one's children.

Doing splendidly if they have in them mere images of virtue

Cicero, On Duties, Book I, p.20

Since we do not live with men who are perfect and clearly wise, but with those who are doing splendidly if the have in them mere images of virtue, I think that we must understand this too: no one should be wholly neglected if any indication of virtue appears in him; moreover, one must particularly foster those who are most graced with the gentler virtues, modesty, restraint and [justice]...for a brave and great spirit in a man who is not perfect nor wise is generally too impetuous; but those other virtues seem rather to attach themselves to a good man.

Screwing your workers and giving to charity

Cicero, On Duties, Book I, p.19

Those who, in order to be liberal towards some, harm others, fall into the same injustice as if they had converted someone else's possessions to their own account. There are, though, many especially those greedy for renown and glory, who steal from one group the very money that they lavish upon another.

Promises should not be kept if they are disadvantageous to those to whom you have made them

Cicero, On Duties, Book I, p.13.

Nor, if they harm you more than they benefit the person who you have promised, is it contrary to good to prefer the greater good to the lesser. For example, if you had made an appointment to appear for someone as advocate in the near future, and in the meantime your son had fallen seriously ill, it would not be contrary to your duty not to do as you had said. Rather, the person to whom you had made the promise would be failing in his duty if he complained that he had been abandoned. Again, who does not see that if someone is forced to make a promise through fear, or deceived into it by trickery, the promise ought not stand?

Cicero is suggesting that the unethical behavior of others may relieve us of the obligation to fulfill out commitments. Where does this sort of reasoning end?

Cicero on premeditated injustice

Cicero, On Duties, Book I, p.12

In every case of injustice it matters a great deal whether the injury was committed through some agitation of the spirit, which is generally brief and momentary, or purposefully and with some forethought. For those things that happen because of some sudden impulse are less serious than those inflicted after reflection and preparation.

Apply some limit

Cicero, On Duties, Book I, p.8

For we shall conserve honorableness and seemliness if we apply some limit and order to the things with which we deal in our life.

The "Crimes and Misdemeanors" challenge

Doesn't it follow from Epicurus that if you are not virtuous and it doesn't bother you, then that's fine too?

Certainly the gods won't intercede to punish you.

You may lack true friends, because you are not just and trustworthy, but what do you care for true friends?

You will suffer guilt and apprehension at your wrong-doing only if you are capable of feeling those emotions. If not, you'll suffer no consequences short of formal, external punishment (and being caught and punished is far from certain).

Epicurus' system does not really account for sociopaths - except to say that it is always good to find ways to protect yourself from other men (acknowledging that there are bad people out there).