Some sentences are true at one world but not at another. For example, one way you could have the block world is for there to be only one block named d$,$ and it is a large tetrahedron, and another way you could have a block world is for there to be only one block named d$,$ and it is a small cube. So$,$ this shows that the sentence Tet$($d$)$ is true at one world but not at another.

Could a sentence that is a logical truth be true at one possible world and false at another?