The central moral principles of justice require us to give proper respect to one another : Each of us must recognize the other as a person and not merely as an object. Each of us may testify. The least common denominator among us is that we are all human beings. In addition to that, we each have particular features making us all unique. Justice pays proper attention to what we have in common and to what sets us apart.

In discussing justice as a personal virtue, Aristotle said that being just, “ is a mean between committing injustice and suffering it, since the one is having more than one’s share, while the other is having less .” As recklessness and cowardice are opposing vices of courage, arrogance and servility are opposing vices of justice.

From sidewalk sexual harassment to the obstruction of justice, all abuses of power involve an unjust willingness to greedily arrogate more than one’s due. Typically, those who abuse their strength or cheat, and then don’t get caught or punished, self-deceptively think they’ve “beaten the system” and “won.” But fooling others into thinking you have earned a victory is not the same as genuinely being victorious. Cheaters fool themselves when they elide this difference.

The other way to fail justice is by judging ourselves to be less worthy than we truly are. This is sadly common among oppressed people, but it also arises among the affluent and powerful under the guise of the “impostor syndrome.” Humility has its place, but we shouldn’t overdo it, nor let it interfere with the intellectual courage required to call out injustice. Those who unfairly put themselves down or are servile, for whatever reason, are doing themselves an injustice by willfully accepting less than their fair share.

Given all this, the virtue of justice plays an important role in families and friendships, between neighbors and citizens, colleagues and clients, acquaintances and strangers. But it is also central to being a good person and living happily, and not merely deceiving oneself into believing that one is a good person and that one is happy.

Bringing justice fully into our lives, thinking in terms of it, will make us more circumspect. We are all too fallible. But it is often the case that we are much better at spotting the faults of others than we are at spotting faults in ourselves. Our blind spots are conveniently located to keep us from seeing our own weaknesses. What a coincidence!

Life is neither just nor fair: Good things happen to bad people and bad things happen to good people. This, however, only increases our obligation to be as just and fair as we can be, to be honest with ourselves as well as others, to try to correct injustice when we see it, and to do as much right in this unfair world as we can.

Paul Bloomfield is a professor of philosophy at the University of Connecticut and the author of “The Virtues of Happiness.”

Now in print: “Modern Ethics in 77 Arguments,” and “The Stone Reader: Modern Philosophy in 133 Arguments,” with essays from the series, edited by Peter Catapano and Simon Critchley, published by Liveright Books.

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