		HOL: Higher-Order Logic

This directory contains the Standard ML sources of the Isabelle system for
Higher-Order Logic.  Important files include

ROOT.ML -- loads all source files.  Enter an ML image containing Pure
Isabelle and type:    use "ROOT.ML";

Makefile    -- compiles the files under Poly/ML and builds a database
Makefile.NJ -- compiles the files under SML of New Jersey and builds a binary

ex -- subdirectory containing examples.  To execute them, enter an ML image
containing HOL and type:    use "ex/ROOT.ML";

Useful references on Higher-Order Logic:

	P. B. Andrews,
	An Introduction to Mathematical Logic and Type Theory
	(Academic Press, 1986).

	J. Lambek and P. J. Scott,
	Introduction to Higher Order Categorical Logic (CUP, 1986)
