(Note: This blog turns six years old today. During these six years, we have posted over 2300 times–2309 to be exact–or an average of 385 posts per year.)
Thus far, we have explored H.L.A. Hart’s influential solution to the demarcation problem in law. (I also recently discovered this good overview of Hart’s contributions by Maryam Akram.) I now want to describe and defend an alternative approach, Oliver Wendell Holmes’s prediction theory of law (PTL). But before I do, I want to acknowledge at the outset that Holmes’s legal theory is, in the words of one contemporary legal philosopher, “nearly friendless.” (See Leslie Green, “Law and Obligations,” in The Oxford Handbook of Jurisprudence and Philosophy of Law, p. 517, quoted in Stephen E. Sachs, “Finding Law,” p. 555, n. 190. Alas, Professor Green’s excellent essay is gated, but Professor Sach’s thoughtful paper is available here.)
To be fair (and intellectually honest), there is a good reason why Holmes’s prediction theory is so unpopular among legal scholars: it is unable to explain how the law works from an “internal point of view,” to borrow Hart’s memorable terminology. Simply put: the prediction theory is incomplete at best because it does not accurately describe or realistically depict how judges actually decide cases. Although Holmes’s theory might explain how lawyers see the law when they are advising clients, i.e. it might describe the law from an external point of view, it can’t explain how legal officials themselves look at the law. For example, a judge who must resolve a dispute or decide a point of law–or a legislator who must decide whether to vote yea or nay on a given bill–isn’t trying to predict his own actions. I will address this powerful criticism of the prediction theory of law in my next two posts.

Image Credit: Maryam Akram
I remember it more fondly, if dimly, as the Pragmatic Theory of Law …
Yes, I could see how the prediction theory of law could be seen as a branch of pragmatism, but there are many variants of “pragmatism.” In any case, rest assured that I will discuss Richard Posner’s variety of legal pragmatism in my next post (6 July 2019).
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