Nicomachean Ethics
Aristotle · -340
"The right way to live isn't defined by following rules or calculating outcomes, but by cultivating virtues — stable character traits, each a mean between two vices of excess and deficiency — through repeated practice, until acting well becomes second nature."
Aristotle's approach to ethics starts from a different question than Mill's or Kant's: not what makes a single action right, but what makes a person good, on the theory that a genuinely virtuous person will reliably do the right thing without needing to run a calculation or consult a rule each time. His central mechanism is the doctrine of the mean: every virtue sits between two failure modes, an excess and a deficiency — courage, for instance, is the mean between cowardice, a deficiency of courage, and recklessness, an excess of courage, and it takes practical wisdom to judge where that mean actually falls in a specific situation.
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Utilitarianism
"The right action is whichever produces the greatest net happiness for the greatest number of people affected — an act is judged entirely by its consequences, not by the intentions behind it or any rule it follows."