We may arrive at a definition of Prudence by considering who are the persons whom we call prudent. Now it is held to be the mark of a prudent man to be able to deliberate well about what is good and advantageous for himself, not in some one department, for instance what is good for his health or strength, but what is advantageous as a means to the good life in general. This is proved by the fact that we also speak of people as prudent or wise in some particular thing, when they calculate well with a view to attaining some particular end of value (other than those ends which are the object of an art); so that the prudent man in general will be the man who is good at deliberating in general. But no one deliberates about things that cannot vary, nor about things not within his power to do. Hence inasmuch as scientific knowledge involves demonstration, whereas things whose fundamental principles are variable are not capable of demonstration, because everything about them is variable, 1140band inasmuch as one cannot deliberate about things that are of necessity, it follows that Prudence is not the same as Science. Nor can it be the same as Art. It is not Science, because matters of conduct admit of variation; and not Art, because doing and making are generically different,¹ since making aims at an end distinct from the act of making, whereas in doing the end cannot be other than the act itself: doing well² is in itself the end. It remains therefore that it is a truth-attaining rational quality, concerned with action in relation to things that are good and bad for human beings. Hence men like Pericles are deemed prudent, because they possess a faculty of discerning what things are good for themselves and for mankind and that is our conception of an expert in Domestic Economy or Political Science. (This also accounts for the word Temperance,³ which signifies “preserving prudence.” And Temperance does in fact preserve our belief as to our own good; for pleasure and pain do not destroy or pervert all beliefs, for instance, the belief that the three angles of a triangle are, or are not, together equal to two right angles, but only beliefs concerning action. The first principles of action are the end to which our acts are means; but a man corrupted by a love of pleasure or fear of pain, entirely fails to discern any first principle,⁴ and cannot see that he ought to choose and do everything as a means to this end, and for its sake; for vice tends to destroy the sense of principle.⁵) It therefore follows that Prudence is a truth-attaining rational quality, concerned with action in relation to the things that are good for human beings. Moreover, we can speak of excellence in Art,⁶ but not of excellence in Prudence. Also in Art voluntary error is not so bad as involuntary, whereas in the sphere of Prudence it is worse, as it is in the sphere of the virtues. It is therefore clear that Prudence is an excellence or virtue, and not an Art. Of the two parts of the soul possessed of reason, Prudence must be the virtue of one, namely, the part that forms opinions⁷; for Opinion deals with that which can vary, and so does Prudence. But yet Prudence is not a rational quality merely, as shown by the fact that a purely rational faculty can be forgotten, whereas a failure in Prudence is not a mere lapse of memory.⁸

Scientific Knowledge is a mode of conception dealing with universals and things that are of necessity; and demonstrated truths and all scientific knowledge (since this involves reasoning) are derived from first principles. Consequently the first principles from which scientific truths are derived cannot themselves be reached by Science; nor yet are they apprehended by Art, nor by Prudence. To be matter of Scientific Knowledge a truth must be demonstrated by deduction from other truths; 1141awhile Art and Prudence are concerned only with things that admit of variation. Nor is Wisdom the knowledge of first principles either⁹: for the philosopher has to arrive at some things by demonstration.¹⁰ If then the qualities whereby we attain truth,¹¹ and are never led into falsehood, whether about things invariable or things variable, are scientific Knowledge, Prudence, Wisdom, and Intelligence, and if the quality which enables us to apprehend first principles cannot be any one among three of these, namely Scientific Knowledge, Prudence, and Wisdom, it remains that first principles must be apprehended by Intelligence.¹²

The term Wisdom is employed in the arts to denote those men who are the most perfect masters of their art, for instance, it is applied to Pheidias as a sculptor and to Polycleitus as a statuary. In this use then Wisdom merely signifies artistic excellence. But we also think that some people are wise in general and not in one department, not “wise in something else,”¹³ as Homer says in the Margites: Neither a delver nor a ploughman him The Gods had made, nor wise in aught beside. Hence it is clear that Wisdom must be the most perfect of the modes of knowledge. The wise man therefore must not only know the conclusions that follow from his first principles, but also have a true conception of those principles themselves. Hence Wisdom must be a combination of Intelligence and Scientific Knowledge¹⁴: it must be a consummated knowledge¹⁵ of the most exalted¹⁶ objects. For it is absurd to think that Political Science or Prudence is the loftiest kind of knowledge, inasmuch as man is not the highest thing in the world. And as “wholesome” and “good” mean one thing for men and another for fishes, whereas “white” and “straight” mean the same thing always, so everybody would denote the same thing by “wise,” but not by “prudent”; for each kind of beings will describe as prudent, and will entrust itself to, one who can discern its own particular welfare; hence even some of the lower animals are said to be prudent, namely those which display a capacity for forethought as regards their own lives. It is also clear that Wisdom cannot be the same thing as Political Science; for if we are to call knowledge of our own interests wisdom, there will be a number of different kinds of wisdom, one for each species: there cannot be a single such wisdom dealing with the good of all living things, any more than there is one art of medicine for all existing things. It may be argued that man is superior to the other animals, but this makes no difference: since there exist other things far more divine in their nature than man, 1141bfor instance, to mention the most visible, the things¹⁷ of which the celestial system is composed. These considerations therefore show that Wisdom is both Scientific Knowledge and Intuitive Intelligence as regards the things of the most exalted¹⁸ nature. This is why people say that men like Anaxagoras and Thales¹⁹ “may be wise but are not prudent,” when they see them display ignorance of their own interests; and while admitting them to possess a knowledge that is rare, marvellous, difficult and even superhuman, they yet declare this knowledge to be useless, because these sages do not seek to know the things that are good for human beings. Prudence on the other hand is concerned with the affairs of men, and with things that can be the object of deliberation. For we say that to deliberate well is the most characteristic function of the prudent man; but no one deliberates about things that cannot vary nor yet about variable things that are not a means to some end, and that end a good attainable by action; and a good deliberator in general is a man who can arrive by calculation at the best of the goods attainable by man. Nor is Prudence a knowledge of general principles only: it must also take account of particular facts, since it is concerned with action, and action deals with particular things. This is why men who are ignorant of general principles are sometimes more successful in action than others who know them: ²⁰ for instance, if a man knows that light meat is easily digested and therefore wholesome, but does not know what kinds of meat are light, he will not be so likely to restore you to health as a man who merely knows that chicken is wholesome; and in other matters men of experience are more successful than theorists. And Prudence is concerned with action, so one requires both forms of it, or indeed knowledge of particular facts even more than knowledge of general principles. Though here too there must be some supreme directing faculty.²¹

Prudence is indeed the same quality of mind as Political Science, though their essence is different.²² Of Prudence as regards the state, one kind, as supreme and directive, is called Legislative Science²³; the other, as dealing with particular occurrences, has the name, Political Science, that really belongs to both kinds. The latter is concerned with action and deliberation (for a parliamentary enactment is a thing to be done, being the last step²⁴ in a deliberative process), and this is why it is only those persons who deal with particular facts who are spoken of as “taking part in politics,” because it is only they who perform actions, like the workmen in an industry.²⁵ Prudence also is commonly understood to mean especially that kind of wisdom which is concerned with oneself, the individual; and this is given the name, Prudence, which really belongs to all the kinds, while the others are distinguished as Domestic Economy, Legislature, and Political Science, the latter being subdivided into Deliberative Science and Judicial Science. Now knowledge of one’s own interest will certainly be one kind of Prudence; though it is very different from the other kinds, 1142aand people think that the man who knows and minds his own business is prudent, and that politicians are busybodies: thus Euripides writes— Would that be prudent? when I might have lived A quiet life, a cipher in the crowd, Sharing the common fortune. . . Restless, aspiring, busy men of action. . .²⁶ For people seek their own good, and suppose that it is right to do so. Hence this belief has caused the word “prudent” to mean those who are wise in their own interest. Yet probably as a matter of fact a man cannot pursue his own welfare without Domestic Economy and even Politics. Moreover, even the proper conduct of one’s own affairs is a difficult problem, and requires consideration. A further proof of what has been said²⁷ is, that although the young may be experts in geometry and mathematics and similar branches of knowledge, we do not consider that a young man can have Prudence. The reason is that Prudence includes a knowledge of particular facts, and this is derived from experience, which a young man does not a possess; for experience is the fruit of years.²⁸ (One might indeed further enquire why it is that, though a boy may be a mathematician, he cannot be a metaphysician or a natural philosopher.²⁹ Perhaps the answer is that Mathematics deals with abstractions, whereas the first principles of Metaphysics and Natural Philosophy are derived from experience: the young can only repeat them without conviction of their truth,³⁰ whereas the formal concepts of Mathematics are easily understood.) Again, in deliberation there is a double possibility of error: you may go wrong either in your general principle or in your particular fact: for instance, either in asserting that all heavy water is unwholesome, or that the particular water in question is heavy. And it is clear that Prudence is not the same as Scientific Knowledge: for as has been said, it apprehends ultimate particular things, since the thing to be done is an ultimate particular thing.³¹ Prudence then stands opposite to Intelligence; for Intelligence³² apprehends definitions, which cannot be proved by reasoning, while Prudence deals with the ultimate particular thing, which cannot be apprehended by Scientific Knowledge, but only by perception: not the perception of the special senses,³³ but the sort of intuition whereby we perceive that the ultimate figure in mathematics is a triangle³⁴; for there, too, there will be a stop.³⁵ But the term perception applies in a fuller sense to mathematical intuition than to Prudence; the practical intuition of the latter belongs to a different species.³⁶³⁷