On Binary Methods
				  by
	     Kim Bruce, Luca Cardelli, Giuseppe Castagna,
		      The Hopkins Objects Group,
		 Gary T. Leavens, and Benjamin Pierce


			       Abstract
Giving types to binary methods causes significant problems for
object-oriented language designers and programmers.  This paper offers
a comprehensive description of the problems arising from typing binary
methods, and collects and contrasts diverse views and solutions.  
It summarizes the current debate on the problem of binary
methods for a wide audience.