For a person to have an opinion about what constitutes justice is for them to demonstrate an understanding of the concept of justice (assuming their opinion is cogent). So, if people are disagreeing about what precisely justice is, it actually means that they do understand the concept of justice.

This is spot on. For concreteness, let me give a candidate definition for the virtue of justice:

Justice - rendering to each person what is owed to them.

It's obvious that we will very often disagree about 'what is owed', but doesn't our passionate disagreement in this case show that (1) we agree that practicing justice is good and (2) we are closely aligned on the existence of this thing called 'justice'?

While I personally agree with the spirit of your definition (though I think it's incomplete) I don't think it's universal even amongst humans. You don't have to look far to see societies or people for whom "what is owed" isn't applicable. Eg. your conventional fascist society where justice means "what I have the power to do/take" (hence the Russia/Ukraine situation).

Lots of conceptions of justice don’t align with your definition, which centers individuals: Climate Justice, (some types of) Social Justice, etc.

I don't think the definition falls apart just because you might owe more than one person the same thing.

For instance, in climate justice we might say that we owe something to all of the people who are young now or haven't been born yet. In social justice you might owe something to a whole group of people. Just because they're groups doesn't mean the individual people that comprise the group dissolve into an abstract concept, even if that's how it might seem in our minds.

In some cases maybe the definition is too narrow because it depends on what is or isn't a "person" which we might define too narrowly. Do we owe things to animals? I'd say so, and I think most people would agree, depending on the animal. Do we owe things to plants? Maybe. Do we owe things to the planet Mars, assuming it's entirely devoid of life? I don't know, but I think it would offend people's sensibilities if we were to dump toxic waste all over it's surface, even if we were sure that humans are never going to settle there or use any of its resources. There's a view of climate justice that we owe things to the Earth directly rather than (or in addition to) owing something to the people that live there or will live there.

Gotcha. I did preface this definition with the word 'candidate' and I acknowledge that there may be good alternate formulations. The spirit of this particular exchange is about whether or not 'justice' can be formulated as a universal.

I shared an argument above for why it can be viewed as a universal and judging by your comment above you are somewhat skeptical of this claim.

If we shift the discussion to allow conceptions of 'justice' that move away from the classical tradition and include modern ideas like 'climate' justice or 'social' justice, I will revert to agreeing with your skepticism.

I don't think anyone can plausibly claim that these more marxist-oriented modern definitions are universals.

> what is owed

This is extremely subjective.

Right. You are touching on the central point of the comment.

Also, there have been a lot of historical disagreements over who or what exactly is a "person", some of which continue to this day.

Maybe for some highly abstract definition of justice. But for more everyday use, it's not hard to come up with examples that one society considers just while the other unjust.

Justice does not have to be cogent, which is defined as "(of an argument or case) clear, logical, and convincing.". There were and are justice systems that leave out one or more of these ingredients to some extent. Some leave out some logic by presuming the existence of a supernatural being. Some are more authoritarian and not very convincing.

I agree with you so I was trying to think of some counter examples and the one that comes to mind would be species that have hive minds? Is justice as important if the many are considered part of the whole? If I drop a stone on my foot and lose my foot, justice is not involved

But “the concept of justice” is not universal, because it really cannot be understood outside the context of law.

> it really cannot be understood outside the context of law

What do you mean by that?

There is no justice outside (or without) law.

I disagree. As long as I have a personal concept of 'good' and 'bad', and prefer it when 'good' things to happen to 'good' people (and vice versa) then I have a concept of justice.

Often, what is good for some is bad for others (and vice versa). Justice would be way too relative (subjective) outside law, so as to be devoid of any meaning, actually.

Laws are relative as well, they differ in every country. Why would justice only exist in another relative system? You know vigilante justice is a well accepted concept that exists outside of the law by definition.

> [laws] differ

So does the definition of justice.

> vigilante justice

Except 'vigilante justice' and 'justice' are concepts that have little to do with each other. You might as well be talking about the 'de facto law' (like for instance the "law" enforced by the local mafia) vs. the 'de jure law' here.

> Except 'vigilante justice' and 'justice' are concepts that have little to do with each other.

That depends on how well different people's definitions of justice line up. There are many things that vigilantes can enforce pretty well.

> You might as well be talking about the 'de facto law' (like for instance the "law" enforced by the local mafia) vs. the 'de jure law' here.

Sure, why not? Mafia law is often not justice, but I think it qualifies as law where sufficiently powerful. You seem to think this argument debunks itself?

Reputation and peer pressure are pretty effective at compelling people to act justly (according to the local consensus definition) even in the absence of a formal legal system.

If reputation and peer pressure scaled to group sizes bigger than Dunbar's number (i.e. about a hundred or so) then we probably wouldn't need laws at all.

I suppose you one might say that social expectations are just another kind of law, in which case, yeah it's hard to imagine any group of people without some kind of expectations of how each other will behave. That's kind of the basis of human relationships.

I can imagine a perfectly just society with no laws.

I, on the other hand, cannot. (I can imagine many strange things, but not this one.)

Consider:

* A society of one.

* A society of one family isolated in nature, where each member is allowed to express their peculiarities and eccentricities, but never do each other any harm - not because of established rules, but because they truly love and care of each other.

One person is not a society.

The second example is virtually unreal (and even expressions of 'love' and 'care' can be harmful).

"Virtually unreal"? It's how humans evolved for hundred thousands years.

Tit-for-tat is a highly effective strategy when playing an iterated-prisoner's dilemma[0]... ie the "concept of justice" can emerge through natural selection if "intelligent beings" were forced to play such games on which their survival depends (a plausible model of "society").

[0] https://en.wikipedia.org/wiki/Prisoner%27s_dilemma#The_itera...

> we should definitely bet against the proposition that "all intelligent beings" understand it

Hey, we can always claim that those who disagree with us are not intelligent.

I'm only partially joking. Lots of today's "justices" have so many internal contradictions that I feel like we should separate them into their own category.