Lat. Inauspicious. Applied. in the Roman law, to a day on which it was unlawful to open the courts or administer justice. Ncgatio conclnsionis est error in lege. Wing. 208. The denial of a conclusion is error in law Ncgatio destruit negationem, et am- bse faciunt affirmationem. A negative destroys a negative, and both make an affirmative. Co. Litt. 140h. Lord Coke cites this as a rule of grammatical construction , not always applying in law. Negatio duplex est affirmatio. A double negative is an affirmative.