R4RS 6.5.5  (= number1 number2 ...)   ==>  boolean
            (< number1 number2 ...)   ==>  boolean
            (> number1 number2 ...)   ==>  boolean
            (<= number1 number2 ...)  ==>  boolean
            (>= number1 number2 ...)  ==>  boolean

These procedures return #T if their arguments are (respectively):
equal, monotonically increasing, monotonically decreasing, monotonically
nondecreasing, or monotonically nonincreasing.

These predicates are required to be transitive.
