From: jaffer@ai.mit.edu (Aubrey Jaffer) Date: Wed, 12 Dec 90 13:13:35 -0500 The scheme spec does not specify the minimum number of arguments for =, <, >, <=, >=. If 0 or 1 argument is acceptable, I assume that these functions should return #t. R3.99RS specifies quite clearly that each of those procedures requires at least two arguments.