“Justice is founded once for all upon the whole of human nature, which, if we know it, binds men together in a common society.”Cicero · Despre îndatoriri · -44 · cartea I, paragraful 22
Justice is not a local bargain, but the law of nature binding us all into one community.
Cicero opposes the idea that justice is merely a local agreement, valid in one city and false in another. His argument: humans are made for sociability, sharing reason and language, so there is a natural law valid everywhere. From this it follows that wronging someone violates your own nature, not just a written statute. One example: even an enemy has a right to a fair trial.
If justice flows from our shared nature, then it does not stop at your city's border. Cicero pushes this logic to its end: the community of rational beings is not local, but universal. A neighbor and a stranger from another continent are, in the end, equally bound to you. Think of an earthquake: people help from the rubble without asking for a passport. This openness is not sentimentality, but a consequence of the reason we share. Yet if we all belong to one community, a hard question arises: to whom do we owe more — the person near us or the one far away?
Why it matters In debates about human rights, the line offers the classical grounding: justice is not negotiated from culture to culture but follows from what we are.