Justice's Two Sides
John Stewart Mill
Utilitarianism

The author contends that when different principles of justice conflict, the disputes are often unresolvable on their own terms, leaving social utility as the only rational arbiter.

...ravate it. On the contrary side it is contended, that society receives more from the more efficient labourer; that his services being more useful, society owes him a larger return for them; that a greater share of the joint result is actually his work, and not to allow his claim to it is a kind of robbery; that if he is only to receive as much as others, he can only be justly required to produce as much, and to give a smaller amount of time and exertion, proportioned to his superior efficiency.
Who shall decide between these appeals to conflicting principles of justice? Justice has in this case two sides to it, which it is impossible to bring into harmony, and the two disputants have chosen opposite sides; the one looks to what it is just that the individual should receive, the other to what it is just that the community should give. Each, from his own point of view, is unanswerable; and any choice between them, on grounds of justice, must be perfectly arbitrary. Social utility alone can decide the preference.
How many, again, and how irreconcileable, are the standards of justice to which reference is made in discussing the repartition of taxation. One opinion is, that payment to the State should be in numerical proportion to pecuniary means. Others think that justice dictates what they term graduated taxation; taking a higher percentage from those who have more to spare. In point of natural justice a strong case might be made for disregarding means altogether, and taking the same absolute sum (when...
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John Stewart Mill

Utilitarianism

Conflicting Obligations

This excerpt directly agrees with the parent text by asserting that when moral obligations conflict, utility serves as the ultimate standard to decide between them, extending the idea that social utility alone can resolve such disputes.

...re of human affairs, that rules of conduct cannot be so framed as to require no exceptions, and that hardly any kind of action can safely be laid down as either always obligatory or always condemnable. There is no ethical creed which does not temper the rigidity of its laws, by giving a certain latitude, under the moral responsibility of the agent, for accommodation to peculiarities of circumstances; and under every creed, at the opening thus made, self-deception and dishonest casuistry get in.
There exists no moral system under which there do not arise unequivocal cases of conflicting obligation. These are the real difficulties, the knotty points both in the theory of ethics, and in the conscientious guidance of personal conduct. They are overcome practically with greater or with less success according to the intellect and virtue of the individual; but it can hardly be pretended that any one will be the less qualified for dealing with them, from possessing an ultimate standard to which conflicting rights and duties can be referred. If utility is the ultimate source of moral obligati...
Though the application of the standard may be difficult, it is better than none at all: while in other systems, the moral laws all claiming independent authority, there is no common umpire entitled to interfere between them; their claims to precedence one over another rest on little better than sophistry, and unless determined, as they generally are, by the unacknowledged influence of considerations of utility, afford a free scope for the action of personal desires and partialities. We must rem...

Aristotle

Nicomachean Ethics

Justice as Equal Mean

Aristotle defines justice as a proportional mean, suggesting that quarrels arise from misapplied equality, thereby implying a non-arbitrary standard of justice that could decide between conflicting claims, challenging Mill's assertion that any choice on grounds of justice is arbitrary.

...dultery, poisoning, pimping, kidnapping of slaves, assassination, false witness; or accompanied with open violence; as insult, bonds, death, plundering, maiming, foul language, slanderous abuse. Chapter VI. Well, the unjust man we have said is unequal, and the abstract “Unjust” unequal: further, it is plain that there is some mean of the unequal, that is to say, the equal or exact half (because in whatever action there is the greater and the less there is also the equal, i.e. the exact half).
If then the Unjust is unequal the Just is equal, which all must allow without further proof: and as the equal is a mean the Just must be also a mean. Now the equal implies two terms at least: it follows then that the Just is both a mean and equal, and these to certain persons; and, in so far as it is a mean, between certain things (that is, the greater and the less), and, so far as it is equal, between two, and in so far as it is just it is so to certain persons. The Just then must imply four terms at least, for those to which it is just are two, and the terms representing the things are two....
Again, the necessity of this equality of ratios is shown by the common phrase “according to rate,” for all agree that the Just in distributions ought to be according to some rate: but what that rate is to be, all do not agree; the democrats are for freedom, oligarchs for wealth, others for nobleness of birth, and the aristocratic party for virtue. The Just, then, is a certain proportionable thing. For proportion does not apply merely to number in the abstract,[10] but to number generally, sinc...

John Stewart Mill

Utilitarianism

Justice as Widened Retaliation

Mill explains the sentiment of justice as originating in an animal desire to repel harm, widened by sympathy to include all persons. This psychological account provides a driving mechanism for why justice manifests both as an individual claim and a community obligation.

...ly deciding on the morality of the act. Otherwise he uses words without a meaning: for, that a rule even of utter selfishness could not possibly be adopted by all rational beings--that there is any insuperable obstacle in the nature of things to its adoption--cannot be even plausibly maintained. To give any meaning to Kant's principle, the sense put upon it must be, that we ought to shape our conduct by a rule which all rational beings might adopt with benefit to their collective interest.
To recapitulate: the idea of justice supposes two things; a rule of conduct, and a sentiment which sanctions the rule. The first must be supposed common to all mankind, and intended for their good. The other (the sentiment) is a desire that punishment may be suffered by those who infringe the rule. There is involved, in addition, the conception of some definite person who suffers by the infringement; whose rights (to use the expression appropriated to the case) are violated by it. And the sentiment of justice appears to me to be, the animal desire to repel or retaliate a hurt or damage to ones...
I have, throughout, treated the idea of a right residing in the injured person, and violated by the injury, not as a separate element in the composition of the idea and sentiment, but as one of the forms in which the other two elements clothe themselves. These elements are, a hurt to some assignable person or persons on the one hand, and a demand for punishment on the other. An examination of our own minds, I think, will show, that these two things include all that we mean when we speak of v...

Blaise Pascal

Pensees

Might's Justification

Pascal reframes the basis of social decision-making from utility to might, arguing that because men cannot make might obey justice, they justify obeying might, thus shifting the lens from calculating happiness to acknowledging power and necessity.

...hout might is gainsaid, because there are always offenders; might without justice is condemned. We must then combine justice and might, and for this end make what is just strong, or what is strong just. Justice is subject to dispute; might is easily recognised and is not disputed. So we cannot give might to justice, because might has gainsaid justice, and has declared that it is she herself who is just. And thus being unable to make what is just strong, we have made what is strong just. 299
The only universal rules are the laws of the country in ordinary affairs, and of the majority in others. Whence comes this? From the might which is in them. Hence it comes that kings, who have power of a different kind, do not follow the majority of their ministers. No doubt equality of goods is just; but, being unable to cause might to obey justice, men have made it just to obey might. Unable to strengthen justice, they have justified might; so that the just and the strong should unite, and there should be peace, which is the sovereign good.
300 "When a strong man armed keepeth his goods, his goods are in peace."[119] 301 Why do we follow the majority? It is because they have more reason? No, because they have more power. Why do we follow the ancient laws and opinions? Is it because they are more sound? No, but because they are unique, and remove from us the root of difference. 302 ... It is the effect of might, not of custom. For those who are capable of originality are few; the greater number will only follow, and refus...

David Hume

An Enquiry Concerning Human Understanding

Judgement's Uncertain Balance

Hume emphasizes the uncertainty inherent in human judgments when experience is not uniform, leading to contrariety and diminished assurance. This questions our ability to settle disputes definitively, aligning with the parent's epistemological concerns.

...inherent in human nature, we should never repose the least confidence in human testimony. A man delirious, or noted for falsehood and villany, has no manner of authority with us. And as the evidence, derived from witnesses and human testimony, is founded on past experience, so it varies with the experience, and is regarded either as a proof or a probability, according as the conjunction between any particular kind of report and any kind of object has been found to be constant or variable.
There are a number of circumstances to be taken into consideration in all judgements of this kind; and the ultimate standard, by which we determine all disputes, that may arise concerning them, is always derived from experience and observation. Where this experience is not entirely uniform on any side, it is attended with an unavoidable contrariety in our judgements, and with the same opposition and mutual destruction of argument as in every other kind of evidence. We frequently hesitate concerning the reports of others. We balance the opposite circumstances, which cause any doubt or uncertain...
89. This contrariety of evidence, in the present case, may be derived from several different causes; from the opposition of contrary testimony; from the character or number of the witnesses; from the manner of their delivering their testimony; or from the union of all these circumstances. We entertain a suspicion concerning any matter of fact, when the witnesses contradict each other; when they are but few, or of a doubtful character; when they have an interest in what they affirm; when they d...

Aristotle

Nicomachean Ethics

The Judge as Mean

Aristotle provides practical guidance for adjudication, instructing judges to restore equality by taking from the excess and adding to the deficit, offering a concrete method for resolving disputes in line with principles of justice.

...given a blow, and loss to him who has received it: still, when the suffering has been estimated, the one is called loss and the other gain. And so the equal is a mean between the more and the less, which represent gain and loss in contrary ways (I mean, that the more of good and the less of evil is gain, the less of good and the more of evil is loss): between which the equal was stated to be a mean, which equal we say is Just: and so the Corrective Just must be the mean between loss and gain.
And this is the reason why, upon a dispute arising, men have recourse to the judge: going to the judge is in fact going to the Just, for the judge is meant to be the personification of the Just. And men seek a judge as one in the mean, which is expressed in a name given by some to judges (μεσίδιοι, or middle-men) under the notion that if they can hit on the mean they shall hit on the Just. The Just is then surely a mean since the judge is also. So it is the office of a judge to make things equal, and the line, as it were, having been unequally divided, he takes from the greater part that by wh...
And when the whole is divided into two exactly equal portions then men say they have their own, when they have gotten the equal; and the equal is a mean between the greater and the less according to arithmetical equality. This, by the way, accounts for the etymology of the term by which we in Greek express the ideas of Just and Judge; (δίκαιον quasi δίχαιον, that is in two parts, and δικάστης quasi διχάστης, he who divides into two parts). For when from one of two equal magnitudes somewhat has...