I would like to concur with Wesley J. Smith's hope that talk about equality will be a saving grace in our public discourse by providing a basis on which virtually everyone can agree, but I think that there is little basis for this hope.
The reason that virtually everyone agrees on a principle of equality is that the principle is being stated at a level of great abstraction, as, for example, in Wesley's quotation from Justice Cardozo, that each life "must be held as equal to that of any other, the mightiest and the lowliest." Everyone can agree with this in just the same way that everyone can agree that human well-being is important, that human beings have dignity, and that we ought to treat others as we would like to be treated. Such statements of philosophical principles entail nothing in practice until they are given much more definite content, and any agreement there may have been when the grand principle was announced will dissolve as soon as the content of those principles begins to be specified.
Ronald Dworkin, for example, begins his treatment of equality in his book Sovereign Virtue (see my review for First Things here) with what he calls the Principle of Equal Importance, which he formulates as "it is important . . . that human lives be successful rather than wasted, and this is equally important . . . for each human life," or "government must act to make the lives of citizens better, and must act with equal concern for the life of each member" of the community. Who could disagree? The problem, of course, is that Dworkin thinks that these principles entail his usual litany of conclusions, which they do notunless he smuggles in a great many other philosophical premises that do all the real philosophical work. When we disagree with his conclusions, incidentally, it is because we have different philosophical premises that we would use to give a rather different content toif we must have such a thingthe Principle of Equal Importance.
So, regrettably, I don't think appeals to grand principles, whether of equality or any other norm, do us much good. The near universal verbal agreement on such principles obscures the more important disagreements about what the content of such principles actually is. We would do better, I think, to be clear about which premises, exactly, lead us to disagree with our opponents, and then turn the argument to which party can produce the better justification for its respective premises.
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