Thucydides’s Melian Dialogue: Can International Politics Be Fair?

In the political philosophy of international relations, a very broad distinction can be drawn between ‘realists’, who foresee perpetual conflict on the world stage, and ‘idealists’, who emphasize cooperation.

Realists tend to operate according to the following assumptions:

1. Human beings are inherently self-interested. Nations of human beings will thus operate solely according to their own self-interest.
2. A nation’s self-interest is fundamentally tied to its security. Given there is no real overarching authority or international law enforcement, nations will actively seek to consolidate their own strength by undermining each other’s.
3. Ethics, justice, and rules have no force or place in the ‘anarchy’ of international relations: they are convenient ad-hoc justifications for a nation’s self-interested conduct. The only real currency is power.

Idealists, by contrast, champion values like international law, collective security, national self-determination, and a belief that if justice is threatened in one part of the world it threatens justice everywhere else.

In the long run, say idealists, it’s in everyone’s interest, even the most powerful nations’, to base international politics on rules derived from principles of justice.

One of the earliest examples of the debate between a realist and idealist conception of international relations comes from the ancient Greek Thucydides’s History of the Peloponnesian War.

Thucydides’s Melian Dialogue, a key part of the History, relates the events of 416 BCE, when Athens invaded the island of Melos.

Thucydides presents the Athenians as basing their logic on a ‘realist’ conception of international relations. It is only right that they capture Melos, they reason, for doing so will consolidate their own security by sending a message to other islands in the region: Athens is not to be messed with.

The dialogue begins with Athenian envoys urging the Melians to realize that their only choice is between destruction and surrender. Do not appeal to justice, say the envoys; in the face of our might, such appeals are irrelevant. Think only of your survival, they implore:

We both know that the decisions about justice are made in human discussions only when both sides are under equal compulsion, but when one side is stronger, it gets as much as it can, and the weak must accept that.

The Melians, however, do not see the choice as between surrender or destruction; they see it as between subjection or war. They love their country, and they don’t want to give up their freedom: despite being militarily weaker, they announce their intention to defend themselves.

While the Athenians told them there was no point in appealing to justice, and to be guided only by self-interest and survival, the Melians suggest principles of justice are irrevocably bound up with self-interest:

[I]n our view (since you force us to leave justice out of account and to confine ourselves to self-interest) — in our view it is at any rate useful that you should not destroy a principle that is to the general good of all men — namely, that in the case of all who fall into danger there should be such a thing as fair play and just dealing, and that such people should be allowed to use and to profit by arguments that fail short of a mathematical accuracy. And this is a principle which affects you as much as anybody, since your own fall would be visited by the most terrible vengeance and would be an example to the world.

Were the Athenian empire to crumble, what hope could the Athenians have of fair dealing, ask the Melians, if they had not upheld just principles themselves?

The Athenians remained unmoved by the Melian argument and went on to conquer the island. Eventually, however, they miscalculated: they overextended themselves and were defeated in the Peloponnesian War by Sparta.

As the scholar W. Julian Korab-Karpowicz summarizes in the SEP’s Political Realism in International Relations:

Drunk with the prospect of glory and gain, after conquering Melos, the Athenians engage in a war against Sicily. They pay no attention to the Melian argument that considerations of justice are useful to all in the longer run. And, as the Athenians overestimate their strength and in the end lose the war, their self-interested logic proves to be very shortsighted indeed.

While Thucydides does not appear to come down in favor of the Athenians’ cynicism nor the Melians’ idealism, one of the overarching lessons of the History of the Peloponnesian War is that, left unchecked, power leads only to an uncontrolled desire for more power.

Unrestrained by moderation or a sense of justice, notes Korab-Karpowicz, there “are no logical limits to the size of an empire.”

International political scholar Jack Donnelly, in his book Realism and International Relations, concludes that Thucydides thus warns us to guard against both “naïve-dreaming on international politics” as well as “the other pernicious extreme: unrestrained cynicism.”

Though Thucydides wrote the History of the Peloponnesian War almost 2,500 years ago, his distinction between these two modes of thought still informs opposing conceptions of international relations today: (1) The only real currency on the world stage is power vs. (2) A nation acting unjustly undermines its own long-term interests and security…

Which position do you lean towards?

• Are you a realist about international politics?
• Do you think embracing idealistic principles ultimately benefits everyone?
• Is there a middle path?

To inform your answers, you might enjoy the following related articles:

• Isaiah Berlin On Why the Pursuit of the Ideal is Dangerous
• Hannah Arendt: 5 Insights into Totalitarianism
• John Rawls: How a ‘Veil of Ignorance’ Can Help Us Build a Just Society
• Catherine of Siena on How Wealth Corrupts Justice
• Political Philosophy: the Best 14 Books to Read

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