In logic, a 'premise' is sent ahead of the conclusion — in property law, it refers to what was already described.
A proposition from which another is inferred or follows as a conclusion; (plural, premises) a house or building together with its grounds, especially as a place of business.
From Old French premisse and Medieval Latin praemissa (proposition set before, thing sent in advance), feminine past participle of Latin praemittere (to send ahead, to put before), composed of prae- (before, in front of) + mittere (to send, to let go), from PIE *meyth₂- (to exchange, to give and take). The logical sense is direct: in a syllogism, the premises are the propositions sent ahead of the conclusion, the groundwork that comes before and supports what follows. The property sense arose from legal documents where the premises (plural) were the lands, buildings, and property described and set forth earlier in the deed — what lawyers called the premises of the document were the particulars
The 'premises' of a building and the 'premise' of an argument are the same word. In legal deeds, the opening section would describe the property being transferred, labeled the 'premises' — the things 'set forth previously' in the document. Over time, 'premises' shifted from meaning 'the things previously mentioned in this deed' to meaning the actual buildings and land described. A logical premise and a business premises are both 'things sent ahead.'