What is "presumption of fact"

Presumption \Pre*sump"tion\ (?; 215), n. [L. praesumptio: cf. F. pr['e]somption, OF. also presumpcion. See Presume.]

1. The act of presuming, or believing upon probable evidence; the act of assuming or taking for granted; belief upon incomplete proof.

2. Ground for presuming; evidence probable, but not conclusive; strong probability; reasonable supposition; as, the presumption is that an event has taken place.

3. That which is presumed or assumed; that which is supposed or believed to be real or true, on evidence that is probable but not conclusive. ``In contradiction to these very plausible presumptions.''
   --De Quincey.

4. The act of venturing beyond due beyond due bounds; an overstepping of the bounds of reverence, respect, or courtesy; forward, overconfident, or arrogant opinion or conduct; presumptuousness; arrogance; effrontery.

   Thy son I killed for his presumption.
   --Shak.

   I had the presumption to dedicate to you a very unfinished piece.
   --Dryden.

   Conclusive presumption. See under Conclusive.

   Presumption of fact (Law), an argument of a fact from a fact; an inference as to the existence of one fact not certainly known, from the existence of some other fact known or proved, founded on a previous experience of their connection; supposition of the truth or real existence of something, without direct or positive proof of the fact, but grounded on circumstantial or probable evidence which entitles it to belief.
   --Burrill.
   --Best.
   --Wharton.

   Presumption of law (Law), a postulate applied in advance to all cases of a particular class; e. g., the presumption of innocence and of regularity of records. Such a presumption is rebuttable or irrebuttable.