 One might think that the meanings of terms that denote mathematical or logical relations could not be handled by a causal theory. How could a mental version of the symbol “+” be causally connected to the addition function? How could a mental version of the logical symbol “¬” be causally connected to the negation truth function? The addition function and the negation function are abstract objects. To avoid this problem, causal theories typically acquiesce and maintain that their conditions are merely sufficient conditions on meaning. If an object meets the conditions, then that object bears meaning. But, the conditions are not necessary for meaning, so that representations of abstract objects get their meaning in some other way. Perhaps conceptual role semantics, wherein the meanings of terms are defined in terms of the meanings of other terms, could be made to work for these other theories.