The Unity of Courage and Wisdom in Plato’s Protagoras

Lino Bianco
(University of Malta; e-mail:

Abstract: The doctrine of the unity of the ‘virtues’ is one of the themes in Plato’s dialogues. It is a doctrine which has been extensively studied and with various interpretations to the thesis contained therein. In the Protagoras Socrates argues for the unity of the ‘virtues’ whereby all are one. One cannot have one of these ‘virtues’ without having all of the rest. In 349d-351b he puts the first argument for the unity of courage with wisdom. The purpose of this research is to investigate the relationship between these two ‘virtues’. The key to understand Socrates’ position lies in exposing the confusion which exists in the debate whereby knowledge, which is used interchangeabl for wisdom, is equated to courage.

pdfPDF    Key words:    unity thesis, similarity thesis, biconditionality thesis, virtue, courage, wisdom, knowledge.

  1. Introduction

One of the themes in Plato’s philosophy is the doctrine of the unity of the ‘virtues’. He put forward two broad queries concerning virtues, one relating to their instrumentality and the other relating to their unity. The latter is one of the themes in the Protagoras, a thesis which has been widely interpreted (Vlastos 1972, Penner 1973, Woodruff 1977). In Protagoras (328d-334c), Socrates argued for the unity of justice and piety, of wisdom and self-control, and of self-control and justice.[1] He then put forth two arguments for the unity of courage and wisdom. The first in 349d-351b whilst the second in 358d-360e. This research focuses on the first argument, the subject of notable scholarship (O’Brien 1961, Vlastos 1972, Devereux 1975, Wolfsdorf 2006), which opens by defining the most pivotal term of the debate, namely ‘andreia’. The argument has two parts: Socrates arguing for the identity of courage and knowledge (349e-350c) and Protagoras objecting to same (350c-351b). In the debate, the word ‘sophia’, meaning ‘wisdom’, and the word ‘episteme’, meaning ‘knowledge’, are used interchangeably (Hubbard and Karnofsk 1984: 134). Given the language barrier to read the original text, the translations by Vlastos (1956), Hubbard and Karnofsk (1984), and Taylor (1991) were used.

  1. Terminology

For the ancient Greeks, ‘virtue’, translated as ‘arete’, was a term applied in ethical contexts. It included ‘dikaiosune’ (justice), ‘andreia’ (courage), ‘sophrosune’ (temperance), ‘hosia’ (piety), and ‘sophia’ (wisdom). These are the principal individual ‘virtues’ which Socrates consistently discusses in the dialogues. With respect to ‘andreia’, a translation more faithful in spirit to the original Greek as used by Plato, is ‘manliness’. The English word ‘courage’ does not convey the ‘manly’ dimension which Plato meant, a theme elaborated in the Gorgias (491-2, 512e) and in the Republic (359b, 544-50). Thus, the author shares the opinion of Gosling (1973: 77) who further argued that:

… Plato uses ‘anandros’ (unmanly) as well as ‘deilos’ (cowardly) as the opposite of ‘andreios’, and in contexts that clearly involve a general appeal to lack of prowess. In fact, commonly ‘andreia’ connotes the characteristics of the admirable, successful man usually connoted by ‘arete’ (excellence) prior to Plato, and often by Socrates’ interlocutors in the dialogues.

  1. The Unity of the ‘Virtues’

Did Socrates attempt to provide a satisfactory answer to the question on how the individual ‘virtues’ relate to the whole and to one another? Devereux argues that the position of Socrates in the Laches and Meno is inconsistent with that in the Protagoras (Devereux 1992: 767). He claims that the thesis of unity differs. Referring to Vlastos, Devereux states that (ibid):

… wisdom is regarded in the Protagoras as one of the parts of virtue, along with courage, temperance, justice, and piety. In the Laches on the other hand, although Socrates speaks of the different virtues as parts of a whole, we shall see that there is one important exception: the other virtues are united through in wisdom, and wisdom is regarded not as a part but as the whole of virtue. [2]

Kremm maintains that the conclusion drawn by Devereux is not entirely adequate (2009: 15):

…whereas Devereux is content with referencing external accounts (e.g. those of Xenophon and Aristotle) of the historical Socrates and attributing the problematic areas to an inconsistency in Plato’s representation of that historical figure, I will suggest an interpretation that makes Socrates’ claims self-consistent.

Kremm attempts to redefine what Socrates is arguing for. His resulting position is more akin to Penner’s similarity thesis, although less stringent in order to avoid the complications of a strict interpretation of the said thesis. Kremm’s pursuit is to find a middle ground between the identity and inseparability in Socratic virtue (2009: 15).[3]

A more reconciliatory interpretation of the doctrine of the unity of the ‘virtues’ was advanced by Brickhouse and Smith who claim that (1997: 313):

…Plato’s early dialogues endorse a single, coherent view of the unity of the virtues. … the key to understanding the coherence of Socrates’ view is to recognize all that Socrates requires of a satisfactory answer to his “What is X?” question. We shall argue that one element of a satisfactory answer to this question regarding any of the virtues will be the same for all virtues: it is through the relationship of each virtue to knowledge of good and evil that each may be said to be the same as all of the others, on the one hand. But because a fully satisfactory account of what a given virtue is must also specify its unique product or function, Socrates also believes that some virtues may be regarded as proper parts of some other virtues, or as proper parts of virtue in general, on the other.

Plato’s writings span over a period of nearly half a century.[4] It is widely acknowledged by Platonist that the early works of Plato are the historical Socrates. Devereux attributes the doctrine of the unity of the ‘virtues’ in the Protagoras to Socrates’ position whilst the doctrine put forth in the Laches to be Plato’s own view on the subject (Devereux 1977: 141). No historical documentation supports the fact that Protagoras is a dialogue chronologically written prior to the Laches. On the contrary, classical scholars have attributed both dialogues to early works of Plato (Cornford 1927, Ryle 1967, Guthrie 1975, Menake 2004),[5] that is, they attributed both dialogues as representing Socrates’ opinion. Alfred E. Taylor, the leading early twentieth century British Platonist and author of the seminal publication Plato: The man and his work, includes Laches as a minor Socratic dialogue whilst Protagoras is presented as a later work of Plato.[6] In the opinion of the author of this paper, Protagoras is a dialogue which further develops the doctrine of the virtues contained in the Laches.[7]

  1. Protagoras (349d-351b)

In discussing the unity of the ‘virtues’, Vlastos identified three distinct formulae employed by Socrates, namely the unity thesis, the similarity thesis and the biconditionality thesis (Vlastos 1972: 417-426).[8] Traditional scholars consistently put forth the first formula as the position of Socrates with respect to the unity of the ‘virtues’. The second formula relates to whether a given virtue is like each of the other and like virtue. According to the third formula, the five virtues tantamount to “coextensive classes” (Vlastos 1972: 424);[9] what activates any one of the virtues must activate every one of the virtues, a state of affairs best represented in symbolic form thus:

N[ΛX(V1x ↔ V2x ↔ V3x ↔ V4x ↔ V5x)][10]

where V1 … V5 denote the five virtues.

This formula, according to Vlastos, is Socrates’ main concern in the dialogue, a position challenged by Christopher C. W. Taylor who argues that the biconditionality thesis is subordinate to the similarity thesis (Taylor 1991: 149).[11]

Protagoras accepts that the four virtues of wisdom, temperance, justice and piety, are “fairly like one another”, but insists that ‘andreia’ is something quite different: a man may be outstandingly ‘manly’ and yet lack all the four above-mentioned virtues (349d). Socrates then attempts to prove that there is no need to make this restriction on the general principle that all virtues are identical (349d-350c). He starts by getting Protagoras to state that ‘manly’ is ‘fearless’, that is, they are ready to plunge into dangers which most men are afraid to encounter. Socrates then points out that some ‘fearless’ people cannot be said to be ‘manly’. It is true that ‘manly’ men are ‘fearless’ but the converse is not true. A person who has learnt how to deal with the risks that a hazardous skill such as fighting or driving involves, is much more ‘fearless’ than an inexperienced and not well informed one, that is, wise men (here substituted for the knowledgeable) are more ‘fearless’. The ignorant, who generally are short-sighted and unaware of the consequences, will frequently fail because of technical difficulties. Protagoras remarks that this is not ‘manliness’ but ‘madness’. A person is ‘manly’ when he is aware of the risk that he is about to take. What transforms ‘fearlessness’ to ‘manliness’ is knowledge.

Reference to the commentary of Hubbard and Karnofsky to their translation of Protagoras provides an insight to Socrates’ position. They advance the following logic for Socrates’ argument (1984: 134-135) :[12]

Assumption A: The ‘andreioi’ are ‘tharraleoi’.

Assumption B: All ‘arete’ and so all ‘andreia’ must be ‘kalon’.

Assumption C: ‘Tharros’ is produced by ‘episteme’.

Assumption D: ‘Tharros’ can also be produced by ignorance (‘amathia’).

Conclusion E:  ‘Tharros’, the kind involved in ‘andreia’, must be the effect of ‘episteme’.

They further state that Socrates’ argument ends as follows (1984: 135-136) :

Assumption F: The wise are ‘tharraleoi’.

Assumption G: The ‘tharraleoi’ are ‘andreioi’.

Conclusion H: ‘Sophia’ is (the same as) ‘andreia’.

  1. Critique

To clarify the hermeneutic issues involved in Socrates’ position at (349e-350c) and Protagoras’ objection to it (350c-351b), Wolfsdorf proposes the following outline to Socrates argument (2006: 436) :

(1) Courageous men are confident.

(2) Courage, qua part of excellence, is fine.

(3) Knowledgeable men are confident.

(4) Some without knowledge are confident.

(5) Ignorant confidence is base.

(6) Therefore, courage is knowledge.

From this argument, Wolfsdorf notes that Socrates ‘attempts to identify courage and knowledge on the grounds that both are fine confidence’ (2006: 436).[13] This leads to the main query of the argument: Can one be ‘manly’ and lack ‘sophia’ or ‘episteme’? Adam and Adam are critical of the argument on the basis that there are not necessarily only two kinds of ‘fearlessness’ but many (Adam and Adam 1921: 173, Guthrie 1975: 227-31). Their claim may be challenged by the fact that Socrates nowhere states that there are only two kinds of ‘fearlessness’. Vlastos, on studying Socrates’ concepts of ‘manliness’ and wisdom, is of the opinion that he (Socrates) evidently knew what he wanted to say but he was unable to put it in the right way. By using the premises “All the ‘manly’ are ‘fearless’” and “No ‘fearless’ men who are not wise are ‘manly’” (which were both admitted by Protagoras), Socrates could easily have stated “All the ‘manly’ are wise”, that is, the conclusion of the two premises.[14] This is what he was required to prove. Socrates was right in assuming to prove it, though wrong in the manner he thought he had proved it.

Protagoras’ position is crucial to the discussion. In his proof, Socrates makes use of the fact that the ‘fearless’ are ‘manly’. This statement is the converse of what Protagoras originally claimed. Socrates’ rival noticed this mistake and defended his position from his own point of view on the grounds that the ‘manly’ are ‘fearless’. ‘Manliness’ may be either a result of knowledge or of other circumstances. Therefore, the higher degree of ‘fearlessness’ which a person enjoys as a result of knowledge, is no proof that ‘andreia’ is the same thing as ‘sophia’ or ‘episteme’. Actually, Protagoras claimed that ‘fearlessness’ may be due not to knowledge but to something else, for example the ‘manliness’ acquired by wrestlers is not due to wisdom but due to physical strength. In this air of confusion and disagreement, Socrates commits fallacies and Protagoras, who objects to them, is himself confused. Instead of solving the difficulties, Socrates brought the argument to an end and immediately started another.

  1. Conclusion

In Protagoras (349d-351b), Socrates confuses x : f(y), that is ‘x is a function of y’ or ‘y being a condition for x’, with x : y, that is ‘x being y’. Thus, instead of saying that knowledge is a condition for ‘manliness’, he claims knowledge is ‘manliness’. Socrates, who originally questioned the possibility of teaching virtue, ends up admitting that virtue is knowledge (and hence teachable). On the other hand, Protagoras, who initially claimed that he was able to teach virtue, concludes by admitting that virtue cannot be knowledge.

Confusion exists between the use of the terms ‘sophia’ and ‘episteme’. It seems that wisdom and knowledge are one and the same thing. This is false. A man may be knowledgeable and not wise; another may be wise and not knowledgeable. One may think that he knows whilst he, in fact, does not know. Knowing that one does not know implies that the individual concerned is not knowledgeable. One is wise if he knows that he is not knowledgeable. Knowing that one is not knowledgeable is wisdom. It is true that ‘manliness’ is conditioned (to a certain extent) by knowledge. Without knowledge there is no ‘manliness’. The more a person is knowledgeable, the more he is ‘manly’. No virtue exists in ‘manliness’ if the reason for which ‘manly’ acts are performed is worthless or out of habit.


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[1]     For a concise exposition of this part of the dialogue, vide Taylor 1926: 247-251.

[2]     The word ‘through’ is in italics to faithfully reproduce the quote as per cited publication. This reads as if Deveruex wants to emphasize this word.

[3] For Kremm’s discussion on the identity and inseparability views, vide pp.16-22.

[4] Taylor (1926) is of the opinion that there were long periods in Plato’s life when he did not write any dialogues. A contemporary opposite position is taken by Menake (2004: 278, endnote 1).

[5] The period grouping of the dialogues given in Cornford was followed by Guthrie (1975: 50). Other dialogues attributed to the early period are Apology, Crito, Lysis, Charmides, Euthyphro, Hippias Minor and (?) Major, Georgias, and Ion (ibid).

[6] Taylor (1926) has three chapters (III to V), each covering three dialogues, entitled minor Socratic dialogues. Laches is one such dialogue (pp.57-64). The next two chapters, entitled Socratic dialogues, cover Georgias, Meno, Euthyphro, Apology, and Crito. Chapter X is all dedicated to Protagoras (pp.235-262).

[7]Taylor is inclined to include Protagoras with Plato’s outstanding dialogues, namely Symposium, Phaedo and the Republic (1932: 49).

[8] This publication is reproduced in Vlastos 1973: 221-265. For a concise exposition of Vlastos’ similarity thesis, and problems which it poses, cfr Devereux (1992: 767-773). This point was also noted by Brickhouse and Smith (1997: 315, fn.12).

[9]The version reproduced in Vlastos’ publication Platonic Studies reads “coextensive dispositions” instead of “coextensive classes” (Vlastos 1973: 232).

[10] This formula reads “Necessarily, for all x, iff x is courageous then x is just, iff x is just then x is pious, iff x is pious then x is temperate, iff x is temperate then x is wise” (Vlastos 1973: 232, fn. 26). This note is not included in Vlastos, 1972.

[11] Other authors who argued for a stronger thesis include Penner (1973) and Woodruff (1977).

[12] The word ‘tharraleos’ can be translated as ‘confident/unafraid’ or ‘daring/willing to face danger’. Thus, the noun ‘tharros’ can mean ‘confident/daring’ (Hubbard and Karnofsky 1984: 134). The word ‘kalon’ is usually translated as ‘the beautiful’ or ‘beauty’ (Guthrie 1975: 177).

[13] Wolfsdorf (2006: 437-442) also notes that, historically, scholars had identified three problems with respect to this argument: (i) at Protagoras 350b, (ii) confidence of the knowledgeable and the ignorant, and (iii) knowledge, courage and confidence.

[14] Brickhouse and Smith (1997: 314) argues that if “… any individual virtue-name can be predicated of any individual virtue, we can infer the equivalence thesis: anyone who possesses one individual virtue possesses all of the other individual virtues”.

Philosophia 11/2016, pp. 5-13.