Exact historical dictionary sense
Suppose in Webster's 1913 dictionary
The 1913 record labels suppose as verb. Its source-bounded etymology and selected historical definition appear below.
[F. supposer; pref. sub- under + poser to place; -- corresponding in meaning to L. supponere, suppositum, to put under, to substitute, falsify, counterfeit. See Pose.]
Cross-verified historical senseIn Webster's Revised Unabridged Dictionary (1913), "suppose" is labeled verb. Its etymology is recorded as: "[F. supposer; pref. sub- under + poser to place; -- corresponding in meaning to L. supponere, suppositum, to put under, to substitute, falsify, counterfeit. See Pose.]" The selected historical definition says: "To represent to one's self, or state to another, not as true or real, but as if so, and with a view to some consequence or application which the reality would involve or admit of; to imagine or admit to exist, for the sake of argument or illustration; to assume to be true; as, let us suppose the earth to be the center of the system, what would be the result?"