This argument is valid:
- All semantic truths are knowable to members of the community of language users.
- There are semantic truths that are not knowable to human language users.
- Therefore, there is at least one non-human language user.
- Elizabeth was not old at age n but she was old at age n+1
- Elizabeth was old at age 1 or Elizabeth is not old at age 89.
The most plausible candidate for the non-human language user who is capable of knowing such semantic facts is God. God could institute the fundamental semantic facts of human language and thereby know them.