A consistency error occurs when two otherwise valid values or operations have been specified that are inconsistent with each other. For example, if two modules each import the same predicate from the other, then that is a consistency error. This error classe is an extension to the ISO Prolog standard.
The SICStus_Error term associated with a consistency error is
consistency_error(Goal, Culprit1, Culprit2, Message)
One of the conflicting values/operations.
The other conflicting value/operation.
Additional information, or