These observations perhaps explain why Aquinas, whose writings nearly all come in the form of extremely well organized and systematic treatises, never completed a thematic discussion of politics. His letter On Kingship (written as a favor to the king of Cyprus) comes closest to fitting the description of a political treatise, and yet this brief and unfinished work hardly presents a comprehensive treatment of political philosophy. Even his commentary on Aristotle's Politics is less than half complete, and it is debatable whether this work is even intended to express Aquinas' own political philosophy at all. This does not mean, however, that Aquinas was uninterested in political philosophy or that he simply relied on Aristotle to provide the missing political teaching that Christianity leaves out. Nor does it mean that Aquinas does not have a political teaching. Although it is not expressed in overtly political works, Aquinas' thoughts on political philosophy may be found within treatises that contain discussions of issues with far reaching political implications. In his celebrated Summa Theologiae, for instance, Aquinas engages in long discussions of law, the virtue of justice, the common good, economics, and the basis of morality. Even though not presented in the context of a comprehensive political teaching, these texts provide a crucial insight into Aquinas' understanding of politics and the place of political philosophy within his thought.
The Political Nature of Man
As we have seen, Aquinas mentions that one of the natural goods to which human beings are inclined is "to live in society." This remark presents the ideal point of departure for one of the most important teachings of Thomistic political philosophy, namely, the political nature of man. This doctrine is taken primarily from the first book of Aristotle's Politics upon which Aquinas wrote an extensive commentary (although the commentary is only completed through book 3, chapter 8 of Aristotle's Politics, Aquinas seems to have commented upon what he considered to be the Politics' theoretical core.). Following "the Philosopher" Aquinas believes that political society (civitas) emerges from the needs and aspirations of human nature itself. Thus understood, it is not an invention of human ingenuity (as in the political teachings of modern social contract theorists) nor an artificial construction designed to make up for human nature's shortcomings. It is, rather, a prompting of nature itself that sets humans apart from all other natural creatures. To be sure, political society is not simply given by nature. It is rather something to which human beings naturally aspire and which is necessary for the full perfection of their existence. The capacity for political society is not natural to man, therefore, in the same way as the five senses are natural. The naturalness of politics is more appropriately compared to the naturalness of moral virtue (Commentary on the Politics, Book 1, Lesson 1 ). Even though human beings are inclined to moral virtue, acquiring the virtues nonetheless requires both education and habituation. In the same way, even though human beings are inclined to live in political societies, such societies must still be established, built, and maintained by human industry. To be fully human is to live in political society, and Aquinas makes a great deal of Aristotle's claim that one who is separated from society so as to be completely a-political must be either sub-human or super-human, either a "beast or a god." (Aristotle's Politics, 1253a27; Cf. Aquinas' Commentary, Book 1, Lesson 1 ).
Aquinas admits, of course, that political society is not the only natural community. The family is natural in perhaps an even stronger sense and is prior to political society. The priority of the family, however, is not a priority of importance, since politics aims at a higher and nobler good than the family. It is rather a priority of development. In other words, politics surpasses all other communities in dignity while at the same time depending upon and presupposing the family. On this point Aquinas follows Aristotle's explanation of how political society develops from other lower societies including both the family and the village. The human family comes into existence from the nearly universal tendency of males and females joining together for purposes of procreation. Humans share with other animals (and even plants) a "natural appetite to leave after them another being like themselves," (Commentary on the Politics, Book 1, Lesson 1 ) and immediately see the utility if not the necessity of both parents remaining available to provide for the needs of the children and one another. As families grow in size and number there also seems to be a tendency for them to gravitate towards one another and form villages. The reasons for this are primarily utilitarian. Whereas the household suffices for providing the daily necessities of life, the village is necessary for providing non-daily commodities (Commentary on the Politics, Book 1, Lesson 1 ). What Aquinas and Aristotle seem to have in mind in describing the emergence of the village is the division of labor. Whereas humans can reproduce and survive quite easily in families, life becomes much more productive and affluent when families come together in villages, since one man can now specialize in a certain task while fulfilling his family's remaining material needs through barter and trade.
Despite the village's usefulness to man, it nevertheless leaves him incomplete. This is partly because the village is still relatively small and so the effectiveness of the division of labor remains limited. Much more useful is the conglomeration of several villages, which provides a wider variety of commodities and specializations to be shared by means of exchange (Commentary on the Politics Book 1, Lesson 1 ). This is one reason why the village is eclipsed by political society, which proves much more useful to human beings because of its greater size and much more elaborate governmental structure. There is, however, a far more important reason why political society comes into existence. In addition to yielding greater protection and economic benefits, it also enhances the moral and intellectual lives of human beings. By identifying with a political community, human beings begin to see the world in broader terms than the mere satisfaction of their bodily desires and physical needs. Whereas the residents of the village better serve their individual interests, the goal of the political community becomes the good of the whole, or the common good, which Aquinas claims (following Aristotle) is "better and more divine than the good of the individual." (Commentary on the Politics, Book 1, Lesson 1 ). The political community is thus understood as the first community (larger than the family) for which the individual makes great sacrifices, since it is not merely a larger cooperative venture for mutual economic benefit. It is, rather, the social setting in which man truly finds his highest natural fulfillment. In this sense, the political community, even though not directed to the individual good, better serves the individual by promoting a life of virtue in which human existence can be greatly ennobled. It is in this context that Aquinas argues (again following Aristotle) that although political society originally comes into being for the sake of living, it exists for the sake of "living well." (Commentary on the Politics, Book 1, Lesson 1 ).
Aquinas takes Aristotle's argument that political society transcends the village and completes human social existence to prove that the city is natural. Similar, but not identical, to this claim is Aquinas' further assertion that man is by nature a "civic and social animal." (ST, I-II, 72.4). To support this, Aquinas refers us to Aristotle's observation that human beings are the only animals possessing the ability to exercise speech. Not to be confused with mere voice (vox), speech (loquutio) involves the communication of thoughts and concepts between persons (ST, I-II, 72.4). Whereas voice is found in many different animals that communicate their immediate desires and aversions to one another (seen in the dog's bark and the lion's roar) speech includes a conscious conception of what one is saying (Commentary on the Politics, Book 1, Lecture 1 ). By means of speech, therefore, human beings may collectively deliberate on core civic matters regarding "what is useful and what is harmful," as well as "the just and the unjust." (Commentary on the Politics, Book 1, Lecture 1 ). Whereas other animals exhibit a certain social tendency (as bees instinctively work to preserve their hive), only humans are social in the sense that they cooperate through speech to pursue a common understanding of justice, virtue, and the good. Since speech is the outward expression of his inner rationality, man is political by nature for the same reason he is naturally rational.
The fact that man is a naturally political animal has far-reaching implications. In addition to being a father, a mother, a farmer, or a teacher, a human being is more importantly identified as a citizen. Achieving genuine human excellence, therefore, most always means achieving excellence as a citizen of some political society (Aquinas does mention the possibility that someone's supernatural calling may necessitate that they live outside of political society. As examples of such people, he mentions "John the Baptist and Blessed Anthony the hermit." See his Commentary on the Politics, Book 1, Lecture 1 .). To be sure, the requirements of good citizenship vary from regime to regime, but more generally conceived the good citizen is the one that places the common good above his own private good and acts accordingly. In doing so, such a person exhibits the virtue of legal justice whereby all of his actions are referred in one way or another to the common good of his particular society (ST, II-II, 58.5). Following the progression of Aristotle's discussion of citizenship, however, Aquinas recognizes a certain difficulty in assigning an unqualifiedly high value to citizenship. What sense does it make to speak of a good citizen in a bad regime? One does not need to consider the worst sorts of regimes to see the difficulty inherent in achieving good citizenship. In any regime that is less than perfect there always remains the possibility that promoting the interests of the regime and promoting the common good may not be the same. To be sure, good men are often called to stand up heroically against tyrants (ST, II-II, 42.2, ad 3), but the full potential of the good citizen will never be realized unless he lives in best of all possible regimes. In other words, only in the best regime do the good citizen and the good human being coincide (Commentary on the Politics, Book 3, Lecture 3 ). In fact, even the best regime will fall short of producing a multitude of good citizens, since no society exists where everyone is virtuous (Commentary on the Politics, Book 3, Lecture 3 ).
But what is the best regime? Following Aristotle, Aquinas argues that all regimes can be divided into six basic types, which are determined according to two criteria: how the regime is ruled and whether or not it is ruled justly (i.e., for the common good). As he explains, political rule may be exercised by the multitude, by a select few, or by one person. If the regime is ruled justly, it is called a monarchy or kingship when ruled by one single individual, an aristocracy when ruled by a few, and a polity or republic when ruled by the multitude. If, on the other hand, a regime is ruled unjustly (i.e., for the sake of the ruler(s) and not for the common weal), it is called a tyranny when ruled by one, an oligarchy when ruled by a few, and a democracy when ruled by the multitude (On Kingship, Book 1, Chapter 1; Commentary on the Politics, Book 3, Lecture 6 [393-394]). Simply Stated, the best regime is monarchy. Aquinas' argument for this is drawn from a mixture of philosophical and theological observations. Inasmuch as the goal of any ruler should be the "unity of peace," the regime is better governed by one person rather than by many. For this end is much more efficaciously secured by a single wise authority who is not burdened by having to deliberate with others who may be less wise and who may stand in the way of effective governance. As Aquinas observes in his letter On Kingship, any governing body comprised of many must always strive to act as one in order to move the regime closer to the intended goal. In this sense, therefore, the less perfect regimes tend to imitate monarchy in which unanimity of rule is realized at once and without obstruction (On Kingship, Book 1, Chapter 2). This conclusion is confirmed by the example of nature, which always "does what is best." For the many powers of the human soul are governed by a single power, i.e., reason. A hive of bees is ruled by a single bee, i.e., the queen. And most convincingly of all, the universe is governed by the single authority of God, "Maker and Ruler of all things." As art is called to imitate nature, human society is therefore best that is governed by a single authority of a eminently wise and just monarch who resembles God as much as humanly possible.
Aquinas is well aware, of course, that such a monarch is not always available in political societies, and even where he is available it is not always guaranteed that the conditions will be right to grant him the political authority he ought to wield. Even worse, there is always the danger that the monarch will be corrupted and become a tyrant. In this case the best of all regimes has the greatest tendency to become the worst. This is why, whereas monarchy is the best regime simply speaking, it is not always the best regime in a particular time and place, which is to say it is certainly not always the best possible regime. Therefore, Aquinas outlines in the Summa Theologiae a more modest proposal whereby political rule is somewhat decentralized. The regime that he recommends takes the positive dimensions of all three "good regimes." Whereas it has a monarch at its head, it is also governed by "others" possessing a certain degree of authority who may advise the monarch while curbing any tyrannical tendencies he may have. Finally, Aquinas suggests that the entire multitude of citizens should be responsible for selecting the monarch and should all be candidates for political authority themselves. Whereas the best regime simply speaking is monarchy, the best possible regime seems to be the mixed government that incorporates the positive dimensions of monarchy, aristocracy, and democracy (In the Summa Theologiae, Aquinas appears to use the name of democracy in place of Aristotle's conception of polity.). To support this conclusion, Aquinas is able to cite the Hebrew form of government established by God in the Old Testament. Whereas Moses (and his successors) ruled the Jews as a monarch, there also existed a council of seventy-two elders which provided "an element of aristocracy." Inasmuch as the rulers were selected from among the people, this sacred regime of the Bible also incorporated a certain dimension of democracy (ST, I-II, 105.1).
Biography and history
Aristotle's life was primarily that of a scholar. However, like the other ancient philosophers, it was not the stereotypical ivory tower existence. His father was court physician to Amyntas III of Macedon, so Aristotle grew up in a royal household. Aristotle also knew Philip of Macedon (son of Amyntas III) and there is a tradition that says Aristotle tutored Philip�s son Alexander, who would later be called "the Great" after expanding the Macedonian Empire all the way to what is now India. Clearly, Aristotle had significant firsthand experience with politics, though scholars disagree about how much influence, if any, this experience had on Aristotle's thought. There is certainly no evidence that Alexander's subsequent career was much influenced by Aristotle's teaching, which is uniformly critical of war and conquest as goals for human beings and which praises the intellectual, contemplative lifestyle. It is noteworthy that although Aristotle praises the politically active life, he spent most of his own life in Athens, where he was not a citizen and would not have been allowed to participate directly in politics (although of course anyone who wrote as extensively and well about politics as Aristotle did was likely to be politically influential).
Aristotle studied under Plato at Plato's Academy in Athens, and eventually opened a school of his own (the Lyceum) there. As a scholar, Aristotle had a wide range of interests. He wrote about meteorology, biology, physics, poetry, logic, rhetoric, and politics and ethics, among other subjects. His writings on many of these interests remained definitive for almost two millennia. They remained, and remain, so valuable in part because of the comprehensiveness of his efforts. For example, in order to understand political phenomena, he had his students collect information on the political organization and history of 158 different cities. The Politics makes frequent reference to political events and institutions from many of these cities, drawing on his students' research. Aristotle�s theories about the best ethical and political life are drawn from substantial amounts of empirical research. These studies, and in particular the Constitution of Athens, will be discussed in more detail below (Who Should Rule?). The question of how these writings should be unified into a consistent whole (if that is even possible) is an open one and beyond the scope of this article. This article will not attempt to organize all of Aristotle's work into a coherent whole, but will draw on different texts as they are necessary to complete one version of Aristotle's view of politics.
Politics and ethics
In Book Six of the Ethics Aristotle says that all knowledge can be classified into three categories: theoretical knowledge, practical knowledge, and productive knowledge. Put simply, these kinds of knowledge are distinguished by their aims: theoretical knowledge aims at contemplation, productive knowledge aims at creation, and practical knowledge aims at action. Theoretical knowledge involves the study of truth for its own sake; it is knowledge about things that are unchanging and eternal, and includes things like the principles of logic, physics, and mathematics (at the end of the Ethics Aristotle says that the most excellent human life is one lived in pursuit of this type of knowledge, because this knowledge brings us closest to the divine). The productive and practical sciences, in contrast, address our daily needs as human beings, and have to do with things that can and do change. Productive knowledge means, roughly, know-how; the knowledge of how to make a table or a house or a pair of shoes or how to write a tragedy would be examples of this kind of knowledge. This entry is concerned with practical knowledge, which is the knowledge of how to live and act. According to Aristotle, it is the possession and use of practical knowledge that makes it possible to live a good life. Ethics and politics, which are the practical sciences, deal with human beings as moral agents. Ethics is primarily about the actions of human beings as individuals, and politics is about the actions of human beings in communities, although it is important to remember that for Aristotle the two are closely linked and each influences the other.
The fact that ethics and politics are kinds of practical knowledge has several important consequences. First, it means that Aristotle believes that mere abstract knowledge of ethics and politics is worthless. Practical knowledge is only useful if we act on it; we must act appropriately if we are to be moral. He says at Ethics 1103b25: "The purpose of the present study [of morality] is not, as it is in other inquiries, the attainment of theoretical knowledge: we are not conducting this inquiry in order to know what virtue is, but in order to become good, else there would be no advantage in studying it."
Second, according to Aristotle, only some people can beneficially study politics. Aristotle believes that women and slaves (or at least those who are slaves by nature) can never benefit from the study of politics, and also should not be allowed to participate in politics, about which more will be said later. But there is also a limitation on political study based on age, as a result of the connection between politics and experience: "A young man is not equipped to be a student of politics; for he has no experience in the actions which life demands of him, and these actions form the basis and subject matter of the discussion" (Ethics 1095a2). Aristotle adds that young men will usually act on the basis of their emotions, rather than according to reason, and since acting on practical knowledge requires the use of reason, young men are unequipped to study politics for this reason too. So the study of politics will only be useful to those who have the experience and the mental discipline to benefit from it, and for Aristotle this would have been a relatively small percentage of the population of a city. Even in Athens, the most democratic city in Greece, no more than 15 percent of the population was ever allowed the benefits of citizenship, including political participation. Athenian citizenship was limited to adult males who were not slaves and who had one parent who was an Athenian citizen (sometimes citizenship was further restricted to require both parents to be Athenian citizens). Aristotle does not think this percentage should be increased - if anything, it should be decreased.
Third, Aristotle distinguishes between practical and theoretical knowledge in terms of the level of precision that can be attained when studying them. Political and moral knowledge does not have the same degree of precision or certainty as mathematics. Aristotle says at Ethics 1094b14: "Problems of what is noble and just, which politics examines, present so much variety and irregularity that some people believe that they exist only by convention and not by nature�.Therefore, in a discussion of such subjects, which has to start with a basis of this kind, we must be satisfied to indicate the truth with a rough and general sketch: when the subject and the basis of a discussion consist of matters that hold good only as a general rule, but not always, the conclusions reached must be of the same order." Aristotle does not believe that the noble and the just exist only by convention, any more than, say, the principles of geometry do. However, the principles of geometry are fixed and unchanging. The definition of a point, or a line, or a plane, can be given precisely, and once this definition is known, it is fixed and unchanging for everyone. However, the definition of something like justice can only be known generally; there is no fixed and unchanging definition that will always be correct. This means that unlike philosophers such as Hobbes and Kant, Aristotle does not and in fact cannot give us a fixed set of rules to be followed when ethical and political decisions must be made. Instead he tries to make his students the kind of men who, when confronted with any particular ethical or political decision, will know the correct thing to do, will understand why it is the correct choice, and will choose to do it for that reason. Such a man will know the general rules to be followed, but will also know when and why to deviate from those rules. (I will use "man" and "men" when referring to citizens so that the reader keeps in mind that Aristotle, and the Greeks generally, excluded women from political part icipation. In fact it is not until the mid-19th century that organized attempts to gain the right to vote for women really get underway, and even today in the 21st century there are still many countries which deny women the right to vote or participate in political life).
1. An initial characterization
A priori” and “a posteriori” refer primarily to how, or on what basis, a proposition might be known. In general terms, a proposition is knowable a priori if it is knowable independently of experience, while a proposition knowable a posteriori is knowable on the basis of experience. The distinction between a priori and a posteriori knowledge thus broadly corresponds to the distinction between empirical and nonempirical knowledge.
The a priori/a posteriori distinction is sometimes applied to things other than ways of knowing, for instance, to propositions and arguments. An a priori proposition is one that is knowable a priori and an a priori argument is one the premises of which are a priori propositions. Correspondingly, an a posteriori proposition is knowable a posteriori, while an a posteriori argument is one the premises of which are a posteriori propositions. (An argument is typically regarded as a posteriori if it is comprised of a combination of a priori and a posteriori premises.) The a priori/a posteriori distinction has also been applied to concepts. An a priori concept is one that can be acquired independently of experience, which may – but need not – involve its being innate, while the acquisition of an a posteriori concept requires experience.
The component of knowledge to which the a priori/a posteriori distinction is immediately relevant is that of justification or warrant. (These terms are used synonymously here and refer to the main component of knowledge beyond that of true belief.) To say that a person knows a given proposition a priori is to say that her justification for believing this proposition is independent of experience. According to the traditional view of justification, to be justified in believing something is to have an epistemic reason to support it, a reason for thinking it is true. Thus, to be a priori justified in believing a given proposition is to have a reason for thinking that the proposition is true that does not emerge or derive from experience. By contrast, to be a posteriori justified is to have a reason for thinking that a given proposition is true that does emerge or derive from experience. (See Section 6 below for two accounts of the a priori/a posteriori distinction that do not presuppose this traditional conception of justification.) Examples of a posteriori justification include many ordinary perceptual, memorial, and introspective beliefs, as well as belief in many of the claims of the natural sciences. My belief that it is presently raining, that I administered an exam this morning, that humans tend to dislike pain, that water is H2O, and that dinosaurs existed, are all examples of a posteriori justification. I have good reasons to support each of these claims and these reasons emerge from my own experience or from that of others. These beliefs stand in contrast with the following: all bachelors are unmarried; cubes have six sides; if today is Tuesday then today is not Thursday; red is a color; seven plus five equals twelve. I have good reasons for thinking each of these claims is true, but the reasons do not appear to derive from experience. Rather, I seem able to see or apprehend the truth of these claims just by reflecting on their content.
The description of a priori justification as justification independent of experience is of course entirely negative, for nothing about the positive or actual basis of such justification is revealed. But the examples of a priori justification noted above do suggest a more positive characterization, namely, that a priori justification emerges from pure thought or reason. Once the meaning of the relevant terms is understood, it is evident on the basis of pure thought that if today is Tuesday then today is not Thursday, or when seven is added to five the resulting sum must be twelve. We can thus refine the characterization of a priori justification as follows: one is a priori justified in believing a given proposition if, on the basis of pure thought or reason, one has a reason to think that the proposition is true.
These initial considerations of the a priori/a posteriori distinction suggest a number of important avenues of investigation. For instance, on what kind of experience does a posteriori justification depend? In what sense is a priori justification independent of this kind of experience? And is a more epistemically illuminating account of the positive character of a priori justification available: one that explains how or in virtue of what pure thought or reason might generate epistemic reasons? But before turning to these issues, the a priori/a posteriori distinction must be differentiated from two related distinctions with which it is sometimes confused: analytic/synthetic; and necessary/contingent.
2. The analytic/synthetic distinction
The analytic/synthetic distinction has been explicated in numerous ways and while some have deemed it fundamentally misguided (e.g., Quine 1961), it is still employed by a number of philosophers today. One standard way of marking the distinction, which has its origin in Kant (1781), turns on the notion of conceptual containment. By this account, a proposition is analytic if the predicate concept of the proposition is contained within the subject concept. The claim that all bachelors are unmarried, for instance, is analytic because the concept of being unmarried is included within the concept of a bachelor. By contrast, in synthetic propositions, the predicate concept “amplifies” or adds to the subject concept. The claim, for example, that the sun is approximately 93 million miles from the earth is synthetic because the concept of being located a certain distance from the earth goes beyond or adds to the concept of the sun itself. A related way of drawing the distinction is to say that a proposition is analytic if its truth depends entirely on the definition of its terms (i.e., it is true by definition), while the truth of a synthetic proposition depends not on mere linguistic convention, but on how the world actually is in some respect. The claim that all bachelors are unmarried is true simply by the definition of “bachelor,” while the truth of the claim about the distance between the earth and the sun depends, not merely on the meaning of the term “sun,” but on what this distance actually is.
Some philosophers have equated the analytic with the a priori and the synthetic with the a posteriori. There is, to be sure, a close connection between the concepts. For instance, if the truth of a certain proposition is, say, strictly a matter of the definition of its terms, knowledge of this proposition is unlikely to require experience (rational reflection alone will likely suffice). On the other hand, if the truth of a proposition depends on how the world actually is in some respect, then knowledge of it would seem to require empirical investigation.
Despite this close connection, the two distinctions are not identical. First, the a priori/a posteriori distinction is epistemological: it concerns how, or on what basis, a proposition might be known or justifiably believed. The analytic/synthetic distinction, by contrast, is logical or semantical: it refers to what makes a given proposition true, or to certain intentional relations that obtain between concepts that constitute a proposition.
It is open to question, moreover, whether the a priori even coincides with the analytic or the a posteriori with the synthetic. First, many philosophers have thought that there are (or at least might be) instances of synthetic a priori justification. Consider, for example, the claim that if something is red all over then it is not green all over. Belief in this claim is apparently justifiable independently of experience. Simply by thinking about what it is for something to be red all over, it is immediately clear that a particular object with this quality cannot, at the same time, have the quality of being green all over. But it also seems clear that the proposition in question is not analytic. Being green all over is not part of the definition of being red all over, nor is it included within the concept of being red all over. If examples like this are to be taken at face value, it is a mistake to think that if a proposition is a priori, it must also be analytic.
Second, belief in certain analytic claims is sometimes justifiable by way of testimony and hence is a posteriori. It is possible (even if atypical) for a person to believe that a cube has six sides because this belief was commended to him by someone he knows to be a highly reliable cognitive agent. Such a belief would be a posteriori since it is presumably by experience that the person has received the testimony of the agent and knows it to be reliable. Thus it is also mistaken to think that if a proposition is a posteriori, it must be synthetic.
Third, there is no principled reason for thinking that every proposition must be knowable. Some analytic and some synthetic propositions may simply be unknowable, at least for cognitive agents like us. We may, for instance, simply be conceptually or constitutionally incapable of grasping the meaning of, or the supporting grounds for, certain propositions. If so, a proposition’s being analytic does not entail that it is a priori, nor does a proposition’s being synthetic entail that it is a posteriori.
This raises the question of the sense in which a claim must be knowable if it is to qualify as either a priori or a posteriori. For whom must such a claim be knowable? Any rational being? Any or most rational human beings? God alone? There may be no entirely nonarbitrary way to provide a very precise answer to this question. Nevertheless, it would seem a mistake to define “knowable” so broadly that a proposition could qualify as either a priori or a posteriori if it were knowable only by a very select group of human beings, or perhaps only by a nonhuman or divine being. And yet, the more narrow the definition of “knowable,” the more likely it is that certain propositions will turn out to be unknowable. “Goldbach’s conjecture” – the claim that every even integer greater than two is the sum of two prime numbers – is sometimes cited as an example of a proposition that may be unknowable by any human being (Kripke 1972).
3. The necessary/contingent distinction
A necessary proposition is one the truth value of which remains constant across all possible worlds. Thus a necessarily true proposition is one that is true in every possible world, and a necessarily false proposition is one that is false in every possible world. By contrast, the truth value of contingent propositions is not fixed across all possible worlds: for any contingent proposition, there is at least one possible world in which it is true and at least one possible world in which it is false.
The necessary/contingent distinction is closely related to the a priori/a posteriori distinction. It is reasonable to expect, for instance, that if a given claim is necessary, it must be knowable only a priori. Sense experience can tell us only about the actual world and hence about what is the case; it can say nothing about what must or must not be the case. Contingent claims, on the other hand, would seem to be knowable only a posteriori, since it is unclear how pure thought or reason could tell us anything about the actual world as compared to other possible worlds.
While closely related, these distinctions are not equivalent. The necessary/contingent distinction is metaphysical: it concerns the modal status of propositions. As such, it is clearly distinct from the a priori/a posteriori distinction, which is epistemological. Therefore, even if the two distinctions were to coincide, they would not be identical.
But there are also reasons for thinking that they do not coincide. Some philosophers have argued that there are contingent a priori truths (Kripke 1972; Kitcher 1980b). An example of such a truth is the proposition that the standard meter bar in Paris is one meter long. This claim appears to be knowable a priori since the bar in question defines the length of a meter. And yet it also seems that there are possible worlds in which this claim would be false (e.g., worlds in which the meter bar is damaged or exposed to extreme heat). Comparable arguments have been offered in defense of the claim that there are necessary a posteriori truths. Take, for example, the proposition that water is H2O (ibid.). It is conceivable that this proposition is true across all possible worlds, that is, that in every possible world, water has the molecular structure H2O. But it also appears that this proposition could only be known by empirical means and hence that it is a posteriori. Philosophers disagree about what to make of cases of this sort, but if the above interpretation of them is correct, a proposition’s being a priori does not guarantee that it is necessary, nor does a proposition’s being a posteriori guarantee that it is contingent.
Finally, on the grounds already discussed, there is no obvious reason to deny that certain necessary and certain contingent claims might be unknowable in the relevant sense. If indeed such propositions exist, then the analytic does not coincide with the necessary, nor the synthetic with the contingent.
Relativism is the radical offspring of non-realism, which is itself descended from the idealism of Berkeley and Kant. Non-realism holds that we cannot meaningfully talk about they way things are independent of our experience of them: to use Michael Dummett's formulation, what makes a statement true is not independent of our procedures for deciding it is true. The main argument in favour of non-realism is essentially negative: it avoids the difficulties endemic to metaphysical realism (a.k.a. "objectivism" or "absolutism").
Realists hold that our judgments are true when they accurately describe or correspond to a reality that exists independently of our perceptions, conceptions, theories or desires. On this view, a true statement such as "water contains oxygen" describes a fact about this independent reality. It rests on a scientific model that may be said to "carve nature at the joints". But an obvious question arises: how can we determine that our judgments are true in this sense? The obvious answer is that we test them by making experiments and observations. I say it will snow today, and I test this by watching the sky. I say water contains oxygen and I confirm this by showing that one of the elements separated out by electrolysis supports combustion. When our assertions are decisively confuted by experience, we conclude that they are false—i.e. they describe a state of affairs that does not obtain.
Relativists accept that this is how we normally conceive of truth and falsity—in ordinary usage, the word "true" means something like "corresponds to the facts"--and as an account of our everyday epistemic procedures it is unobjectionable. But they argue that it loses coherence if it is elevated to the metaphysical level. For what is really happening, even when we are confirming the most mundane belief about the empirical world, is that we are satisfying ourselves that this belief coheres with our other beliefs. We confirm that the sea is salty by tasting it or by conducting a chemical analysis of seawater. But these procedures only confirm our belief about sea water in the sense of showing it to be compatible with or even entailed by a host of other beliefs: for instance, that the sample we are examining is typical; that nothing else tastes quite like salt; that our sensory faculties are trustworthy on this occasion; that salt tastes roughly the same at different times. What we can never do, argue relativists and other non-realists, is check the degree of correspondence between our judgments and reality as it is independent of our experience of it. To do this we would have to take a "sideways on" view of the cognitive relation between subject and object. But this is impossible since any vantage point we adopt will necessarily be that of the subject. For the same reason, we cannot compare our overall conceptual scheme or theoretical model of reality with reality as it is "in itself."
The driving idea behind empiricism and the upshot of Kant's critique of speculative metaphysics is thus that concepts must be tied to experience if they are to have legitimate employment in science or philosophy. Relativists argue that the metaphysical realist's concept of truth fails this test, for it takes the notion of "correspondence with reality" out of its everyday employment, where it is genuinely useful, and tries to press it into metaphysical service, where it is neither useful nor legitimate. So even if, in its normal usage, "truth" means something like correspondence with reality, the ultimate criterion of truth turns out to be coherence with other beliefs. To put it another way: our philosophical conception of truth cannot simply be an expanded version of our commonsense notion of truth as correspondence. And this implies that truth must always be relative to some belief system, to some particular epistemic standpoint. This is the first of the two theses identified above as constituting the doctrinal kernel of relativism. Numerous philosophers have affirmed it. Yet many of these have sought to avoid relativism by rejecting the second thesis—that no standpoint is metaphysically privileged over all others.
This second thesis is what gives relativism its bad name. Critics commonly reduce it to the claim that any point of view is as good as any other and then attack it with some variation of Plato's arguments against Protagoras. But virtually no well-known philosophers actually hold that all standpoints are of equal worth. Richard Rorty, for instance, who is widely regarded as a relativist, dismisses that position as "silly." (Richard Rorty, Objectivism, Relativism, and Truth, p. 89). Rorty, Kuhn and most other relativists accept that one can have cogent reasons for preferring one standpoint to another; the preferred point of view may, for instance, exhibit greater logical consistency or greater predictive power than other available perspectives. But they argue that such reasons cannot confer any special metaphysical status on the standpoint in question. They cannot, for instance, show it to be the one favoured by God, or dictated by Reason, or most in accord with human nature.
Relativists typically justify this conclusion along the following lines. Any proof of a standpoint's superiority must rest on premises that express fundamental assumptions and basic values. For instance, arguments for the superiority of the standpoint of modern science over that of religion will presuppose the value of consistency, of solving theoretical puzzles, and of being able to manipulate one's environment. A person who defends the literal truth of the bible but shares these values is likely to be persuaded fairly quickly by these arguments. But a person who holds that truth appears to humans as paradoxical, and who values tradition and religious faith over experimental evidence and predictive power will not be persuaded. An argument can only be convincing to one who accepts its premises. Some premises, though, like those just mentioned, are so fundamental that they are not usually argued for at all. Rather, they are constitutive of a particular outlook.
The relativists' thesis is not that one cannot support standpoints with arguments; it is that in the end all such arguments must be circular since they inevitably rest on premises that are themselves part of the standpoint. Critics will here point out that there is a difference between denying that the superiority of one standpoint over all others can be proved and denying that such a standpoint exists. In reply, relativists are likely to claim that this distinction is an abstract one that no consistent empiricist or pragmatist would make. To insist that one standpoint is objectively superior to all others, they argue, even though there is no way of proving this, is dogmatic and pointless; to claim that one's own standpoint enjoys this unique but undemonstrable superiority is dogmatic and implausible.
A critic might also object that what relativists call "cogent" reasons for preferring one standpoint to another are not epistemically relevant: that is, they do provide grounds for thinking that the standpoint generates or ensures beliefs that are objectively true. But this is clearly a point most relativists would be willing to concede. The notion of objective truth referred to here is not a concept for which they have a use, preferring instead something like William James' conception of truth as "what is good in the way of belief.
a. Relativism is Self-Refuting
A doctrine is self-refuting if its truth implies its falsehood. Relativism asserts that the truth-value of a statement is always relative to some particular standpoint. This implies that the same statement can be both true and false. The qualification that the statement is true relative to standpoint A but false relative to standpoint B may save relativism from the charge of embracing gross contradictions. But it still clearly implies that relativism itself is false, at least relative to some standpoints. One might say that it is just as much false as it is true, in which case there seems to be no good reason to prefer relativism to alternative positions such as realism.
One possible response to this objection would be to modify the theory and hold that all truths are relative except for the truth that all truths are relative. On this view, the relativist thesis enjoys a unique status, being true in some non-relativistic sense. This position may be coherent, but it is rather implausible. It is hard to see what could justify granting the thesis of relativism this exceptional status. A more plausible option is for relativists to concede that their view is false relative to at least some non-relativistic theoretical frameworks but to deny that this admission is damaging. Relativism, they can claim, is simply in the same situation as any other theory. The theory of evolution is true from the perspective of modern science and false from the perspective of Christian fundamentalism. Relativists deny that one of these perspectives is demonstrably better than the other. But this does not mean that they cannot affirm the scientific perspective, and do so for cogent reasons. In the same way, they can acknowledge that relativism is false from the standpoint of metaphysical realism; but they can do this without inconsistency or incoherence since they are not metaphysical realists, and they have reasons for preferring relativism to realism.
A variation on the charge that relativism is self-refuting is the argument that it is somehow self-refuting for relativists to assert or to argue for their position. This line of attack has been pressed forcefully by Hilary Putnam and others. Putnam's argument is that ordinary rational discourse presupposes a non-relativistic notion of truth. Jûrgen Habermas offers a similar sort of argument in his critique of postmodernists like Foucault and Derrida, claiming that a commitment to truth, like a commitment to sincerity, is a necessary condition of successful communication.
Relativists, however, are likely to remain skeptical about these alleged presuppositions and implicit commitments. It may be true that when we engage in rational discourse we implicitly commit ourselves to the truth of what we are saying. But it is not at all obvious that we implicitly commit ourselves to a non-relativistic conception of truth. And even if this were the case, it is not clear why this supposed presupposition of everyday communication should be accorded so much respect and made the basis for a philosophical account of truth. Our everyday notions of space and time may also be non-relativistic, but we do not demand that physicists' theories of space and time conform to our pre-scientific ideas.
b. Relativism has Pernicious Consequences
This criticism also was first ventured by Plato and continues to be endorsed by many. Cognitive relativism is thought to undermine our commitment to improving our ways of thinking rather as moral relativism is thought to undermine our belief in the possibility of moral progress. Several reasons have been given to support this anxiety. To some, the fact that relativism countenances the possibility of multiple true but incompatible points of view entails a kind of epistemic nihilism. If creationism and the theory of evolution, Ptolemaic and Copernican astronomy, astrology and modern psychology are all equally true, then what purpose is served by developing new scientific theories? All views are of equal value, so why not just rest content with whatever happens to be "true for us"?
Against this, relativists can offer two responses. First, truth is not the only epistemic value. We can also prefer theories on the basis of such values as coherence with our other beliefs, predictive power, and practical fruitfulness. Second, by endorsing relativism one does not lose the right to judge beliefs according to their truth or falsity. Modern relativists will believe that the earth orbits the sun and that Copernicus' discovery represented scientific progress over earlier astronomy. But their philosophical account of the status of these beliefs will be relativistic. The Copernican theory is true and its acceptance represents progress according to the values and concerns that constitute the modern scientific standpoint—a standpoint shared by both relativists and non-relativists. The difference between them is that the relativists do not believe this standpoint can be proved superior to others except by arguments that are essentially circular and question-begging.
Hillary Putnam presses a slightly different version of the above objection. Relativism, he argues, tries to "naturalize" the concept of reason. What he means is that relativists try to discuss questions of truth, knowledge, and rationality in a thoroughly descriptive, non-normative way. Like social scientists afraid of allowing value-judgments to creep into their work, they take a detached stance and simply report the epistemic customs and practices of different cultures, eschewing any impulse to endorse or criticize them. And this amounts, in Putnam's words, to "mental suicide". For, while particular norms of rationality will be entrenched within a particular culture, reason has an inalienable critical or transcendent function which can be used to criticize existing epistemic norms. Relativism can thus be accused of encouraging a certain kind of intellectual passivity.
Relativists have also been accused of embracing determinism, and certainly thinkers like Nietzsche and Foucault sometimes invite this charge. The epistemic norms of a culture or a period are taken to be shaped by non-rational forces such as class interests, technology, or the will to power of a group or individual. And what people then come to believe is seen as a function of these norms. For example, Foucault suggests that the classification of homosexuality as a disease results from employing a certain kind of theoretical framework, one that posits a sharp distinction between the natural and the unnatural and correlates the former with the healthy, the latter with the sick. And this framework becomes established because it serves certain interests. So truth is identified with what is believed to be true, and what is believed to be true is determined by larger social forces operating within a culture or historical epoch.
This deterministic tendency, like the attempt to naturalize reason, is held by critics to entail, or at least encourage, a renunciation of the longstanding project of using reason to criticize existing norms, beliefs, and practices in order to furnish ourselves with better ones. Relativism is thus associated with the counter-Enlightenment aspects of postmodernism. But association is not the same thing as logical entailment. It may well be true that some relativists are drawn towards determinism or feel they must eschew value judgments. But it is not clear that these tendencies must be part of a relativistic outlook. Other relativists will argue that the connection between relativism and determinism, say, is historical and contingent rather than logical and necessary. In their view, one can consistently endorse a relativistic view of truth while still being committed to the relative superiority of some views over others, to the value of critical reflection, and to the possibility of using reason as an instrument of scientific and social progress.
Besides the "Big Three" classical pragmatists, there were many other important thinkers labeled (sometimes self-identified) as pragmatist. George Herbert Mead (1863-1931) was particularly influential during the first several decades of the twentieth century, especially in his work on the social development of the self and of language. A generation later, Clarence Irving Lewis (1883-1964) wrote several significant works in the middle third of the twentieth century on what he termed "conceptualistic pragmatism," stressing how pragmatic grounds shape the interpretation of experience. His contemporary, Alain Locke (1885-1954), blending the thought of earlier pragmatists with that of W.E.B. DuBois (1868-1963), produced a large body of work on the social construction of identity (particularly focusing on race) and advocating cultural pluralism within the context of what he called a philosophy of "critical relativism" or “critical pragmatism.”
Another important thinker, often labeled as pragmatist, but noted more for advocating an explicit version of philosophical idealism, was Josiah Royce (1855-1916). Though there were other American idealists (e.g., G. H. Howison of the St. Louis Hegelians and Bordon Parker Bowne (1847-1910), known for his view of "personalism"), Royce is recognized as the most influential of them. Epistemologically, Royce noted that any analysis of experience shows that the fact and, indeed, very possibility of error leads to the postulation of both mind and external reality, since only minds can be in error and being in error presupposes something about which mind can be mistaken. The recognition of error presupposes a higher level of awareness, since knowing that one is in error about X presupposes that one recognize both X and what is mistaken about one's judgment. Error, then, presupposes some form or level of veridicality. Much like the story of the blind men who come upon an elephant, each believing that part of the elephant captures the whole, the message here is that error is really partiality, that is having only partial truth. For Royce, this also pointed to the ultimate communal nature of all interpretation, as knowledge (even of one's self) comes from signs, which in turn require some kind of comparison and finally of community. Royce extended this view, and displayed definite affinities to pragmatism, in his analysis of meaning. The meaning of an idea, he claimed, contained both an external and an internal element, much as we say that terms have both a denotation and a connotation. Ideas have external meaning in the sense that they connect up to an external world. But they have an internal meaning in the sense that they embody or express purpose. What is real, Royce claimed, is "the complete embodiment in individual form and in final fulfillment, of the internal meaning of finite ideas." As these in turn require comparison and moving beyond partiality, they come finally to a complete and coherent absolute level of ideas, what he termed "Absolute Pragmatism.
Ordinary-language philosophy became dominant in analytic philosophy only after World War II—hence the dates for the ordinary-language era given in the Introduction are 1945-1965. Indeed, with the exception of several articles by Ryle, the most important texts of the ordinary-language camp were published in 1949 and later—in some cases not until much later, when the linguistic approach to philosophy in all its forms was already on its way out.
Ordinary-language philosophy is sometimes called “Oxford philosophy.” This is because Ryle, Austin, Strawson and Grice were all Oxford dons. They were the most important representatives of the ordinary-language camp after Wittgenstein (who was at Cambridge). After Wittgenstein died in the early years of the ordinary-language era, they lived to promote it through its heyday.
Despite the strong connection to Oxford, Wittgenstein is usually taken to be the most important of the ordinary-language philosophers. For this reason, we will focus only on his later views in giving a more detailed example of ordinary language philosophy.