Thrasymachus' First Argument
An Argument Analysis and Reconstruction
Contact: Dr. Jan Garrett
Last revised date: September 18, 2003
As of September 18, I have renumbered the steps of the formal version of the argument given at the bottom of this page.
The point of this longish discussion of what seems to be a short argument is to show, as explicitly as possible, how one might think through an argument analysis. The text under discussion is Thrasymachus' view of justice from Plato's Republic, in the translation found in M. Velasquez, Philosophy: A Text with Readings, 8th edition, p. 24 (4th and 5th entry by Thrasymachus)
"Listen up, then. I say that justice is nothing more than whatever is advantageous to the stronger. Well, why don't you praise me. But no, you'd never do that.First, leave aside the parts that don't do any logical work. Following is what would be left in Thrasymachus' argument:"As you must know, Socrates, some nations are ruled by tyrants, others are ruled by a democratic majority, and still others are ruled by a small aristocracy. . . . Whoever rules-the ruling party-is the stronger in each nation . . . . And in each nation, whoever rules passes the laws that are to their own-the rulers' advantage. After they pass these laws, they say that justice is obeying the law. Whoever fails to keep the law is punished as unjust and a lawbreaker. So that, my good man, is what I say justice is. Justice is the same in all nations: whatever is to the advantage of the ruling group. The ruling group, you must admit, is the stronger. So if one reasons correctly, one will conclude that everywhere justice is the same: it is whatever is advantageous to the stronger."
"--- justice is nothing more than whatever is advantageous to the stronger.--Second, pick out the final conclusion. Here the conclusion is clear, it has been stated up front, and it is repeated at the end of the argument. Most of what Thrasymachus says seems to converge on it as alleged justification for it:"---some nations are ruled by tyrants, others are ruled by a democratic majority, and still others are ruled by a small aristocracy. . . . Whoever rules-the ruling party-is the stronger in each nation . . . . And in each nation, whoever rules passes the laws that are to their own-the rulers' advantage. After they pass these laws, they say that justice is obeying the law. Whoever fails to keep the law is punished as unjust and a lawbreaker. So that . . . is what I say justice is. Justice is the same in all nations: whatever is to the advantage of the ruling group. The ruling group --- is the stronger. So --- everywhere justice is the same: it is whatever is advantageous to the stronger."
(C) justice is everywhere whatever is advantageous to the stronger.From the context, we know that "stronger" refers to one of two parts of a society. The two parts are the ruling part and the ruled part. Thrasymachus tells us (it is one of his ultimate premises) that(1) The ruling group or person is the stronger of the parts of a society.Thrasymachus tells us also that(2) the ruling part passes laws that are to its own advantage . . . and punishes those who break the laws.He also says that this is true everywhere. In other words,(3) The ruling part of any nation passes [and enforces] laws that are to its own advantage.(2) is included in (3) and probably can be ignored as an independent step.
(3) is based on alleged observation of three types of regime--tyranny, aristocracy, democracy--and on the unstated assumption that these are the only types.
(3a) In a tyranny the (ruling) tyrant passes [and enforces] laws to his advantage.
(3b) In an aristocracy the (ruling) aristocrats [and enforce] pass laws to their advantage.
(3c) In a democracy the (ruling) masses pass [and enforce] laws to their advantage.
(3d) [assumed] There are no other types of regime.
Therefore
(3) The ruling part of any nation passes [and enforces] laws that are to its own advantage.(3 appeals to 3a, 3b, 3c and 3d, which are ultimate premises.)
We have to get justice into the conclusion, but how? Thrasymachus does this through the connection between law and justice. He tells us that
(4a) the ruling party defines justice as obeying the law.In his own definition of justice "the ruling party defines" drops out. So he must assume that(4b) however all ruling parties agree to define justice is justice.Thus he seems to reason(4a) Every ruling party defines justice as obeying the law
(4b, assumption) However all ruling parties agree on defining justice is the correct definition.
So, (4) justice is obeying the law.[implied intermediate conclusion strongly
suggested by "That is what I say justice is."]Given (4) and (3), one might reasonably conclude that
(5) Justice is everywhere to the advantage of the ruling party.Given (5) and (1) one can plausibly reach the final conclusion that
(C) justice is everywhere [to] the advantage of the stronger.
* * * Now, we can set out a fully formalized reconstruction of the argument. I am using "P" to indicate an ultimate premise, "IC" to indicate an intermediate conclusion, "A" to indicate an assumption, i.e., a premise that is assumed but not stated, and "FC" to indicate final conclusion. At this point I am renumbering the steps, using whole integers, so that the result will be cleaner.
(1, P) The ruling group or person is the stronger of the parts of a society.(2, P) In a tyranny the (ruling) tyrant passes [and enforces] laws to his advantage.
(3, P) In an aristocracy the (ruling) aristocrats [and enforce] pass laws to their advantage.
(4, P) In a democracy the (ruling) masses pass [and enforce] laws to their advantage.
(5, A) There are no other types of regime.So (6, IC) The ruling part of any nation passes [and enforces] laws that are to its own advantage.
(based on 2-5)
(7, P) Every ruling party defines justice as obeying the law
(8, A) However all ruling parties agree on defining justice is the correct definition.
So, (9, IC) justice is obeying the law.(based on 7 and 8)
(10, IC) Justice is everywhere to the advantage of the ruling party.
(based on 6 and 9)
(11, FC) Justice is everywhere [to] the advantage of the stronger.
(based on 1 and 10.)
* * * The point of Argument Analysis and Reconstruction is to set out the structure of the argument, not necessarily to criticize it.
But, having done the Analysis and Reconstruction work correctly (or at least we hope so!), it is not hard to see where the argument might be challenged. For a start, how about step 8? How about 7 for that matter? If either of these premises is false, then 9 and 10 might not be justifiable, and if 10 is unjustified, then 11 has lost one of the two legs on which it stands.
"Based on": That is, the just stated conclusion or intermediate conclusion is meant to receive its logical support directly from these premises.