The Commens Dictionary
Quote from ‘Issues of Pragmaticism’
One who knows that Harvard University has an office in State Street, Boston, and has impression that it is at No. 30, but yet suspects that 50 is the number, would say “I think it is at No. 30, but it may be at No. 50,” or “it is possibly at No. 50.” Thereupon, another, who does not doubt his recollection, might chime in, “It actually is at No. 50,” or simply “it is at No. 50,” or “it is at No. 50, de inesse.” Thereupon, the person who had first asked, what the number was might say, “Since you are so positive, it must be at No. 50,” for “I know the first figure is 5. So, since you are both certain the second is a 0, why 50 it necessarily is.” That is to say, in this most subjective kind of Modality, that which is known by direct recollection is in the Mode of Actuality, the determinate mode.