I’ve posted on SSRN a draft of my Dunbar Lecture in Law and Philosophy,
titled as above, which I will deliver tomorrow at the University of
Mississippi.  The Lecture is sponsored by the Law School and Department
of Philosophy.  When they kindly invited me to deliver the lecture, I
was told that past Dunbar Lecturers had included, as it happens, one of the subjects of my Lecture,
Ronald Dworkin.  The abstract follows:

Ronald Dworkin describes an approach to
how courts should decide cases that he associates with Judge Richard
Posner as a Chicago School of "anti-theoretical, no-nonsense
jurisprudence." Since Professor Dworkin takes his own view of
adjudication to be diametrically opposed to that of the Chicago School,
it might seem fair, then, to describe Dworkin’s own theory as an
instance of "pro-theoretical, nonsense jurisprudence." That
characterization is not one, needless to say, that Professor Dworkin
welcomes. Dworkin describes his preferred approach to jurisprudential
questions, to be sure, as theoretical, in opposition to what he calls
the practical orientation of the Chicago School. But while there is a
real dispute between Dworkin and Posner, it is not one illuminated by
the contrast between theory and practice. It is, rather a dispute about
the kind of theory that is relevant and illuminating when it comes to
law and adjudication. And the fault line marked by this dispute is
profound indeed, one that extends far beyond Dworkin and Posner and has
a venerable and ancient history. I shall describe it, instead, as a
dispute between Moralists and Realists, between those whose starting
point is a theory of how things (morally) ought to be versus those who
begin with a theory of how things really are. The Lecture endeavors to
show that our contemporaries, Ronald Dworkin and Richard Posner, are
reenacting a version of the dispute between the paradigmatic
philosophical moralist Plato and the paradigmatic historical realist
Thucydides.