of "exist" are distinguished: 43   R1: Paris exists. ["Exist", sense E 1 .]   R2: Carthage once existed. ["Exist", sense E 2 .]   R3: Atlantis once existed. ["Exist", sense E 3 .]   R4: Vulcan exists. ["Exist" , sense E 4 .] 44   Naturally, several of the above might