Hillmon appears to contemplate the use of a statement to prove the doing of the intended act by the declarant (Walters) and the doing of the act by a third person (Hillmon), as long as the acts were done in concert. What if Walters' letters were offered to prove it was Hillmon who went with Walters to find a sheep ranch? What if Walters' letters were offered to show Hillmon intended to go with Walters? Would these letters then be admissible?