The Fact-Sensitivity of Political Principles
1
Matthew Noah Smith
Yale University
For the Rocky Mountain Ethics Congress August 2009
1.
By interrogating G.A. Cohen’s recent discussion of the fact-sensitivity of principles, I aim to focus our attention on justification in political philosophy and to suggest what amounts to a hermeneutic approach to theorizing political justification.
2.
G.A. Cohen claims that philosophers often will appeal to some fact, F, about the condition of the world in which we live in order to justify some normative principle, P, governing how we should live (where the set of facts and the set of principles do not share members and the union of the two sets is exhaustive).
2
That is, Cohen claims that some philosophers treat facts as (not necessarily conclusively) justifying many of the principles governing how we should live. Such principles that are susceptible to justification by facts are fact-sensitive principles. Let us represent the relation between a fact and a principle when that fact grounds that principle with the following notation:
F i
j P i
1 Thanks are due to Matt Evans for valuable last-minute discussion. Thanks also to Stephen
Darwall, the participants of the Yale Working Group in Moral Philosophy, and to Thomas Pogge.
2 See G.A. Cohen, “Facts and Principles” 31 Philosophy and Public Affairs 3 (2003): 211 – 245; and G. A. Cohen, Rescuing Justice and Equality (Cambridge, MA: Harvard University Press,
2008), chapter 6 (hereafter RJE).
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Let us call this a “j-schema.” The j-schema above is read as “F i
justifies P i
” or, if appropriate, “F i
partially justifies P i
” or “F i
grounds P i
” or “F i
partially grounds P i
.” 3
An example of this is the following:
P p
: One ought to keep one’s promises.
Suppose A asks, “What justifies P p
?” and B answers, “Promise-keeping is necessary for meaningful, long-term cooperation.” So, in order to justify P p
, B has cited a fact:
F t
: Promise-keeping is necessary for meaningful, long-term cooperation.
That is, B is using the following j-schema to show why one ought to keep one’s promises:
F t
j P p
.
J-schemata do not pick out a determination relationship, such as the fact that this ball hitting the window brought about – determined – the window’s breaking, since such relationships are causal and between facts. J-schemata also need not pick out dependence relationships between facts and principles, where dependence relationships are
3 Cohen is not clear about whether the facts are sufficient to conclusively justify principles, but he often writes as if the targets of his criticism believe this.
2

understood as relationships between x and y when x is a necessary condition for y, although they might.
But, j-schemata do pick out another kind of dependence relationship between a fact and a principle, namely the kind of dependence relationship that exists between a justificatory ground and what is justified or grounded by that justificatory ground. An example of this is the following: the fact that I consented to being subject to your authority justifies the micro-principle that I am obligated to do as you say. This fact might not hold, in which case I would not be obligated to do as you say unless some other fact – e.g., that by doing as you say I will ensure that the best possible outcome occurs – grounds the micro-principle. So, while my being obligated to do as you say depends upon my consenting to being subject to your authority, my consent is not a necessary condition for my being subject to your authority. This weaker notion of dependence can be used interchangeably with the more familiar notion of justification that j-schemata pick out.
Cohen argues that all j-schemata demand explanation: why does F i
(partially) justify P i
? He claims further that the explanations of j-schemata will always take the form of what I shall call an “e-schema,” where the explanans is another principle that does not depend on F i
:
4
P j
e [F i
j P i
] where j ≠ i and it is not the case that F i
j P j
4 Is this a plain-Jane causal explanation of some sort? I presume not, although not because of anything Cohen says (in fact, he says nothing about this). Still, Cohen is explicit that these are explanatory relations and not justificatory.
3

Since Cohen presumes that all j-schemata demand explanation by e-schemata, we can sum up Cohen’s view about the relationship between j-schemata and e-schemata as follows:
(F i
j P i
)

(P j
e [F i
j P i
])
Cohen continues by noting that the principle on the left-hand side of an e-schema might also be on the right-hand side of a j-schema, i.e., that principle might itself be grounded by some fact. If so, then it is featured in a j-schema if and only if there is a corresponding e-schema. This, of course, could go on and on, but Cohen rejects the possibility of a regress. So, we will have eventually to get to a principle that is not featured in a j-schema, which eo ipso makes that principle a fact-insensitive principle.
This, Cohen claims, is our fundamental normative principle, since it is the ground floor explanans of all the j-schemata “above” it.
The notion of explanation Cohen employs here is opaque: could this just be a case of further justification and not something else, namely non-justificatory explanation?
Cohen, in a footnote, insists it is not.
5 I do not know what to make of this, although it doesn’t really matter for the sake of this paper. It is sufficient to understand the principle on the left in an e-schema as in some way rendering transparent – either through justification or some other explanatory process – the justificatory relationship between the fact and the principle in the j-schema contained with the e-schema, where that lefthand principle itself is formally but not materially identical with any other principle figuring in a j-schema. The formal identity referred to here is realized when two
5 CITE
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principles can play similar roles in standard justifications in moral and political philosophy and so both principles have the potential to enter into j-schemata. More concretely, the principle on the left hand side of an e-schema must be a familiar moral or political principle, such as “It is wrong to break promises” or “We ought to treat all persons equally” and not some other principle, such as a principle of epistemic warrant or a principle of aesthetic merit.
So, in sum, we have three main claims:
1.
The justification of a principle by a fact, i.e, the fact-sensitivity of a principle
(represented by a j-schema), demands explanation.
2.
This explanation of fact-sensitivity will always take the form of a principle explaining the justificatory relationship between a fact and a principle.
3.
This process cannot be a regress but must go on until it bottoms out in a principle that is not justified by a fact, i.e., a fact-insensitive principle.
Notice that the first claim employs a version of the principle of sufficient reason while the third claim expresses a methodological commitment to rejecting regresses.
Thus, we get a relation represented by a j-schema that demands explanation, which is in the form of a relation represented by an e-schema. The new principle that is invoked in the e-schema is either fundamental or it is itself fact-sensitive. If the latter, then explanation is required. The resulting regress is fairly straightforward recursion:
F i
j P i
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But, why does that fact justify that principle?
P j
e [F i
j P i
]
But F j
j P j
But, why does that fact justify that principle?
P k
e [F j
j P j
]
And so on.
Recursive regresses are the kind of regresses that we usually worry about and they are usually the kind that are generated by appeals to the general form of a principle of sufficient reason. For example, the cosmological argument for the existence of God makes use of both a PSR-style principle and a philosophical aversion to such regresses: every event has a cause, but this cannot go on forever, so there must have been some uncaused causer doing the initial causing. So, Cohen’s argument takes an age-old and familiar form. But, does it succeed? We have good reasons to think that it does not.
3.
We commonly take grounds, G, for a belief, B, to warrant, w, that belief. Let us represent this with a w-schema :
G i
w B i
We do not normally ask what further principle explains the relation picked out in the w-schema. Rather, we seek to explain why G i
warrants B j by appealing to the nature
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of warrant itself. We do not appeal to some other principle – a principle distinct from a principle of epistemic warrant – to explain why a fact warrants a belief. There might be a regress lurking in here somewhere but the recursive regress of the sort Cohen identifies does not immediately materialize.
Cohen could argue that both G i
and B j are facts, and the regress he is concerned with gets started only when we have a justificatory relationship between facts and principles. But, is this denial of symmetry between w-schemata and j-schemata plausible? The standard relationship between facts is a causal relationship. But, the warranting relation is an unusual case since it is not a causal one. Rather, it is a normative relation – one that involves justification for belief. So, w-schemata represent a normative relationship in more or less the same way that j-schemata do (and that is one reason why the warranting relation is philosophically interesting). So, this way of denying symmetry is blocked even if G i
and B j are facts.
More generally, there seems to be symmetry between facts providing justificatory support for a normative principle and facts providing epistemic warrant for beliefs. For, when the proposition p expresses a political principle (e.g., “Social and economic inequalities are to be arranged so that they are to be of the greatest benefit to the leastadvantaged members of society.”), then warrant for the belief that p should be the same thing as a justification of p (I am putting aside cases where G is a principle). So, it seems that the same opacity plaguing j-schemata which is the source of the demand for explanation plagues w-schemata. This demands some kind of explanation, even if it is not the type of explanation Cohen is apparently committed to endorsing, namely an epistemic warrant version of e-schemata. It is in virtue of the demand for explanation
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and Cohen’s preference for e-schemata-type explanations that triggers the supposedly dangerous regress.
Cohen would therefore be driven to conclude that if there are epistemic norms at all, then there is an epistemic grundnorm just like the foundational political principle he says exists if there are any principles at all. What would such a foundational epistemic principle look like? Perhaps it would be something like Descartes’ principle that we ought to believe only clear and distinct ideas, although this itself rests on another principle, namely that we ought to trust God. Cohen would also be denying that the way in which we explain the relation picked out in w-schemata is via an exploration of the nature of epistemic warrant. Cohen’s also welcome to do this – just as he is welcome to search for an epistemic grundnorm
– but it has substantial philosophical cost, as it runs against the grain of much of epistemology as it is practiced.
So, it is an interesting choice Cohen must make: either he accepts that the warranting relation in epistemology is entirely different than the justifying relation in moral and political philosophy or his argument proves epistemological foundationalism and recommends a methodology unfamiliar to contemporary epistemology. If he goes with the former, then he has a great deal more work to do: he must explore the nature of justification itself, which he doesn’t do, and if he goes with the latter, he must at the very least take on the philosophical burden of making plausible a Cartesian-style foundationalism about knowledge.
4.
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Let us suppose that there is a fact-insensitive principle P k
. Let us suppose that it is justified by another principle, P l
. Let us call the following a j*-schema:
P l
j* P k
Doesn’t this demand explanation just like j-schemata do? There is a definite symmetry here. So, let us suppose that Cohen respects such symmetry (why wouldn’t he?). So, this demand would in turn be answered by the following e*-schema:
P m
e* [P l
j* P k
]
But, we have just introduced a new principle, P m
. And, presumably, P m
is justified by either a principle or a fact. Either way, this new schema, be it a j-schema or a j*-schema, demands explanation, and so a new e*-schema must be generated. A regress of the ugly recursive kind ensues.
Does this mean that Cohen has shown that just as there must be fact-insensitive principles, there must be fundamental principles that resist justification? That is, has
Cohen proven that there are unjustified justifiers? What’s next – God?
Suppose that there are numerous regressions running in parallel. It follows that there will either be many unrelated unjustified justifiers (polytheism!) or a single unjustified justifier unifying all the strands (monotheism!). If Cohen accepts the former, he will have to commit to brute incommensurability of unjustified justifiers such that
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conflicts between unjustified justifiers cannot be adjudicated in a principled manner. If
Cohen goes the latter route then he commits to a fairly straightforward form of Platonism.
How one reacts to this feature of Cohen’s argument depends largely on whether one already believes that there are unjustified justifiers, commensurable or no. Those who are not already disposed to accepting this conclusion will see this as evidence that there is something deeply wrong with Cohen’s approach. Those who go in for unjustified justifiers might see this as a virtue of Cohen’s argument that Cohen – who knows why? – didn’t exploit. All parties should see as philosophically worrisome the ease with which
Cohen establishes such a controversial and profoundly significant conclusion.
5.
The two points just made conspire to raise the concern that Cohen has not really explored with sufficient depth the nature of justification in political philosophy. What
Cohen asks for is something that mediates the connection between grounding facts and fact-grounded principles. (Notice that at this point that Cohen ignores that more facts can mediate the connection between grounding facts and principles – but he is interested only in the principles that mediate the relationships between principle-grounding facts and fact-grounded principles.
6
) And, what Cohen assumes in order for his argument to work
6 This raises a problem for Cohen. If a fact could ultimately explain a j-schema, then maybe what is fundamental in ethics and political philosophy are facts and not principles. But, this is exactly what Cohen aims to disprove. So, Cohen could suggest that such a fact-based explanation is too opaque to be the final explanation and so further explanatory schemata are required, although this asymmetry with the familiar e-schemata is hardly obvious. Or Cohen could simply deny that a fact could explain a j-schema. But, this seems false. Consider a principle requiring promisekeeping:
P pk
: One ought to keep one’s promises.
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is that the principles he assumes are mediating the relationships between grounding facts and fact-grounded principles are somehow external to the elements of the j-schema. That is, these mediating principles are not themselves based in some feature of the j-schema itself; they are not somehow based in the nature of the fact, the principle or the justificatory relationship between the fact and the principle.
For example, it could be the case that what explains the j-schema depends upon the nature of the fact-grounded principle in question. That is, any principle mediating the two elements of the j-schema might amount to a claim about the nature of the factgrounded principle. And to know the nature of that principle is to know what it takes to make that principle true, and so not only that the grounding fact grounds the principle but why the grounding fact grounds the principle.
Let us consider an epistemic analogue first since it provides a clear example of the sort of case I am trying to describe. To begin, then, consider the following epistemic principle:
Suppose this principle is true partially because breaking promises will corrode the social practice of promising:
F sp
: Breaking promises will corrode the social practice of promising.
We therefore get the following j-schema:
F sp
j P pk
This can be read as: One ought to keep one’s promises (at least partially) because breaking promises will corrode the social practice of promising. This j-schema demands explanation. So, consider the following not-obviously false explanation of the j-schema:
The social practice of promising facilitates people engaging in complex, long-term projects.
Thus we get the following e**-schema in which a fact explains why another fact justifies a principle (it is an e**-schema because on the left is a fact and not a principle):
F pr e** [F sp
j P pk
].
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P e
: One ought to believe propositions that the balance of evidence strongly indicates are true.
Here’s a fact that (partially) justifies this principle:
F e
: When the balance of evidence strongly indicates a proposition is true, then the proposition is very likely to be true.
What could explain why this fact justifies this principle? If we consider the nature of belief, we get the answer. It is in the nature of belief for it to aim at the truth. So, we get the following regulative principle governing belief-formation, which straightforwardly mediates the relationship between F e
and P e
:
P b
: Beliefs ought to aim at the truth.
This is not a fact-insensitive principle – the principle follows from the fact that it is in the nature of belief to aim at the truth. If one asks, “But why ought belief aim at the truth?” we can answer, “Because it is the nature of belief to aim at the truth.” And this is just a fact about belief.
7
In this way, a fact can ground the principle that explains a j-
7 Okay, we need to say more. See, e.g., David Velleman, “On the Aim of Belief” in David
Velleman, The Possibility of Practical Reason (Oxford: Oxford University Press, 2000): 244 –
81; David Owens, “Does Belief Have an Aim?” 115
Philosophical Studies (2003): 283 – 305;
Nishi Shah, “How Truth Governs Belief,” 112
Philosophical Review (2003): 447 – 82l; and Nishi
Shah and David Velleman, “Doxastic Deliberation,” 114
Philosophical Review (2005): 497 –
534.
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schema, where that fact is, in the sense just explained, internal to the fact and principles in the e-schema.
8
So, what if it were a fact about fundamental political principles, e.g., principles of justice, that if they were realized in an actual society, then the society would be stable, i.e., not prone to civil wars and revolution?
9
This truth would not be a normative principle in itself in the sense of it being a normative principle picking out stability as a value. It is simply a fact about principles of justice in the same way that it is a fact about beliefs that they aim at the truth. It could even be the case that stability is disvaluable (e.g., because it might make creativity impossible) while at the same time being a necessary component of just societies in virtue of their being just. But, in order to determine what principles of justice will ensure stability in an actual society, we must appeal to facts about the actual society, or at least to facts about how societies could be. Thus, the principle of justice would be fact-sensitive.
10
Another way to look at the issue: what makes some principle of justice a principle of justice and not, e.g., an aesthetic principle, are features that a principle of justice has as a matter it being a principle of justice . In our example, it is a fact about justice that its principles concern human societies in which the realization of principles of justice ensures stability. This is one fact that is not the case when it comes to epistemological
8 Notice that one could say: “It would be better if belief aimed at what made us morally ideal,” but this is a patently different kind of claim than, “Beliefs ought to aim at what makes us morally ideal.” For, the former is a claim about what sort of thing belief ought to be, the latter is a claim about the sort of thing beliefs ought to do. The latter sort of claim, I am arguing, follows from the factual counterpart of the former sort of claim (obviously not the same claim), which in turn is
9 just an expression of the nature of belief.
I don’t think this is true, but it could be. Here’s one I think is true: it is a fact about principles of justice that in a just society, there would be less interpersonal violence than in an unjust society.
10 It would go like this: One reason why P is a principle of justice is the fact, F, that if P is realized in a human society, then that society would be stable.
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and aesthetic principles and so something that distinguishes such principles from political principles. This fact might in turn be the source of a principle that explains the relationship between a principle of justice and a fact in a j-schema. So, a more fundamental fact-insensitive principle that is external to the fact-grounded principle in that j-schema needn’t be called upon to explain why the fact in that j-schema grounds that principle.
We can find support for this line of argument would if we turn our attention to the fundamental principles that Cohen aims to show must exist. For, what it is for some principle to be a fundamental political principle and not, e.g., a fundamental aesthetic or epistemic principle cannot, regardless of whether that principle is fact-sensitive, depend upon a more fundamental principle (since the principle in question is ex hypothesi fundamental). So, it must be the kind of principle it is in virtue of certain facts about it.
But this applies as much at the fundamental level as it does up a level: that which makes it that such-and-such an n-level principle is a principle of justice and not, e.g., an aesthetic or epistemic principle, might also explain why some of what justifies that principle – e.g., facts – can do that justifying work that they do. In short: Some essential feature of a principle can mediate the relationship between that principle and the facts that might provide grounds for that principle. So, we cite that feature in order to explain the j-schema featuring the principle and the grounding fact.
For example, suppose the following is a principle of justice:
P dem
: People ought, through some democratic process, author the laws governing them.
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And suppose that the following fact partially supports this principle:
F stability
: Democratic processes ensure stability.
And if someone asks, “Why does F stability ground P dem
?” one might answer, “People ought to establish stable social orders.” And if someone asks for a justification of this principle, one can cite the following fact: “Because that is just in the nature of justice.” That is, if one knows what justice is, then one will know that a principle of justice is one that, if realized in a social order, would ensure stability.
In short, moral and political principles are what they are in virtue of some facts about them. These facts can in turn be employed to explain why some other fact grounds a principle of that sort. This is not to say that every single j-schema is explained in this fashion. It is surely the case that many – or maybe most – j-schemata are explained by appeal to some further principle that does not itself spring from the nature of the factgrounded principle in the j-schema in question. But, when the threat of regress looms, we ought to check to see whether the j-schema can be explained by a principle that flows from the nature of the fact-grounded principle in the relevant j-schema.
Surprisingly, we can find this line of thought an argument Cohen levels against
Rawls at a later point in his book. Cohen charges Rawls with, in effect, conceptual confusion when he presents the principles that reasoners in the original position choose as principles of justice . Cohen argues that the principles chosen in the original position are
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principles of regulation (alternatively called “all-things considered best principles to live by”) and not principles of justice. Cohen writes with a disapproving tut-tut:
“My objection to that identification is that, simply because they are the all -things considered best principles to live by, optimal all-things-considered principles are therefore not necessarily the best principles considered form the point of view of justice alone.” (RJE 275 – italics in the original)
This point only makes sense if we can find some gloss of “from the point of view of justice alone.” And, the most natural gloss is to treat this “point of view” as defined by facts about justice itself. So, when Cohen objects to the Rawlsian decision procedure, he is objecting to a decision procedure infected with confusion about what justice is – confusion that leads choosers in that decision procedure to mistake certain matters as justice-related when in fact these matters are justice-related only contingently. Thus,
Cohen writes
“Rawlsians believe that the correct answer to the question ‘What is justice?’ is identical to the answer that specially designed choosers, the denizens of the
Rawlsian original position, would give to the question ‘What general rules of regulation for society would you choose, in your particular condition of knowledge and ignorance?’” (RJE 277)
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What is striking here is that Cohen is arguing in a similar fashion I have just described, except instead of ruling in certain considerations, he is ruling them out (but on formally identical grounds). Cohen is arguing that if the Rawlsians understood what justice was then they would know that there is no explanation available for, i.e., no true eschema that included, a j-schema according to which the fact that some principle would successfully regulate common life grounds a principle of justice, and so any such jschema would have to be rejected due to lack of explanation.
This point is reinforced by Cohen’s assertion later in the text that in order for choosers in the original position (or any ideal reasoner in a constructivist account of justice) to determine which principles are principles of justice, the reasoners must possess already some grasp of what justice is. This knowledge allows them to determine which facts support the principles they are considering (alternatively: it allows them to determine why certain facts ground the principles they are considering and why certain facts do not so ground those principles).
Notice, then, that this does not involve appeal to deeper principles or fact insensitive principles but simply to knowledge about what the object of inquiry is. That is, if one knows everything there is to know about the nature of justice, one knows more than the principles of justice and the combination of facts and principles that together justify those principles, one knows why those facts and principles together justify those principles. All this follows from the nature of justice, which includes the nature of the enterprise of justifying principles of justice. So, if the reason why those facts and principles together justify those principles is itself a principle, then that principle follows from the nature of justice. The regress is thereby avoided.
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This is part of the significance, in fact, of Rawls’ remarkable initial pages of
Theory of Justice , in which he offers the conceptual underpinning for any constructivist project. One might reject – and many have rejected – Rawls’ account of the requirements for a successful theory of justice – namely that a theory of justice is a theory of the first principles of a society and that these principles regulate the basic institutions of the society by governing the distribution of the benefits and burdens of social cooperation.
But, something like this is minimally necessary for going about the project of generating principles of justice. And, such criteria are determined not by appeal to deeper, possibly fact-insensitive principles, but by appeal to facts about the nature of justice. And, that is where the debate must be joined.
These reflections follow from more general reflections about the nature of grounding claims – claims that something is so in virtue of something else. While it is surely the case that in some instances principles that explain j-schemata will be principles that do not follow from the nature of the fact-grounded principle in the j-schemata, Cohen presumes that this will always be the case. But he has offered no reason to accept this presumption.
6.
This discussion has highlighted an additional approach to challenging Cohen’s account. As already noted, we have discovered a problematic feature of Cohen’s argument through an interrogation of the nature of the grounding relationship represented by j-schemata. We have not questioned whether there is something distinct to grounding relationships involving moral and political principles . As Cohen notes, the grounding
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relationship between a fact and a principle grounded by that fact is not translucent – we cannot see through the relationship in a way that obviates the need for an explanation of its existence. As I suggested in Section Four, though, the grounding relation that exists between two principles may fail to be translucent as well: an explanation of j*-schemata is demanded by the same opacity we find in grounding relationships represented by jschemata. Thus, we can conclude that there is a general question about what makes it the case that a fact or a principle grounds, supports, justifies, etc., a(nother) principle.
One way that some have resolved this question is by arguing that norms of correctness for justification in political philosophy might be such that the explanation of why some fact justifies some principle involves appeal to the nature of the fact-grounded principle itself. No argument of the form Cohen gives can rule out a norm of correctness of this sort. For that matter, no argument of the form Cohen gives can rule out a norm of correctness according to which, e.g., j-schema judgments are correct if they can withstand a procedure of scrutiny from some constructed standpoint. And, this is just the sort of claim that a constructivist might make about the nature of justification in moral and political philosophy: if a fact grounds a moral or political principle, then it does so in virtue of it meeting certain standards set by the project of political justification.
APPENDIX: Some Candidate Principles Following from the Nature of Justice
Here are two principles that might follow from the nature of justice and so explain why some fact grounds a principle of justice. I present them in order to show how we might derive an explanation of a j-schema from the nature of a principle of justice. I do not present them in order to defend them at length.
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(a) Usefulness
Suppose that a principle of justice, to be a principle of justice, must be useful for those who understand that principle. In particular, it must be possible for the principle to be useful, as opposed to it being probably that it’s useful, which is a much higher bar.
For example, if all who understand the principle for some reason are failing to see how the principle would be useful because everyone is spending too much time watching TV and playing video games, then the principle could be useful (if only the subjects stopped being so lazy). So, the mere fact of general laziness preventing people from finding a principle of justice useful would not count against the principle of justice being a principle of justice . On the other hand, if it simply were biologically impossible for beings who understood the principle to use it (e.g., the principle requires, as a matter of justice, that physically distinct beings unite into a single massive being), then the principle would be useless and, according to the requirement imagined here, it would not be a principle of justice . In this way, this requirement makes it the case that principles of justice would be sensitive to certain facts, facts about our biology, for example.
Perhaps other normative principles, e.g., utopian normative principles, wouldn’t be such that a usefulness requirement would follow from their natures, but if we assume that principles of justice are not utopian, then this point is moot. In general, denying the usefulness requirement involves claiming that it is part of the nature of justice that it could be utterly useless for beings like us, which means that it is no argument against a principle of justice that since it, e.g., requires us to liquefy ourselves into separate globs of sentient goop and then unify into a single lump of sentient goop, the principle requires
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that we do the impossible and not merely the improbable. But, this sort of argument seems to carry a lot of weight: we seem to have a prima facie reason to reject any principle of justice that requires the (physically/biologically/psychologically) impossible.
11
(b) Knowability
It is natural to suppose that no matter how their social orders are organized, insects cannot have unjust social orders. One explanation of this claim is that insects cannot understand principles of justice and ipso facto cannot know principles of justice.
Why is this an explanation? Because it follows from the nature of justice that its principles are in principle knowable by those to whom they apply, i.e., a principle of justice, to be a principle of justice, must be in principle knowable by those who are governed by it.
For the sake of argument, suppose that there is a principle of justice so complex that human beings cannot understand it (because we are cognitively limited beings and this principle, because of its awesomeness, is something only God, because of God’s omnipotence, can understand). Is it possible that we are doomed forever not to know whether we live in an unjust society because it is impossible for us to understand what the true principle of justice is? It is possible, but many who engage in political philosophy pursue the practice under the following assumption: “If there is a true principle of justice, then it will be understandable for at least some human beings.” That is, they operate as if the knowability requirement follows from the nature of justice. This, in itself, merely
11 It is utterly ad hoc to rule out principles on the basis of their requiring certain impossibilities – e.g., meeting the sentient glob requirement – while not ruling out others on the basis of their requiring other impossibilities – e.g., meeting an extreme beneficence requirement.
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hints at a performative contradiction made by those who deny that it follows from the nature of justice that it is knowable but who nonetheless operate as if the nature of justice is knowable. Thus, even though I have no argument for why we ought to accept that the knowability requirement follows from the nature of justice, certain features of our practice of political philosophy suggests grounds for not rejecting that the knowability requirement follows from the nature of justice.
Notice that arguing against the knowability requirement becomes much more difficult given that we are competent users of the concept of justice. So, we must imagine that we are competent users of the concept but nonetheless cannot and hence never will (and not that we merely are not likely to) come to know what the substantive principles of justice are. Such dumbfounding is possible when it comes to natural kinds that play roles in our best physical theories (e.g., it may be impossible for us every to know much about the nature of black holes), but there is reason to doubt that this could be the case when it comes to normative political principles such as justice.
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