Rate; proportion; degree. Reason, or understanding. Also a cause, or giving judgment therein. Ratio decidendi. The ground of decision. The point in a case which determines the judgment. Ratio legis. The reason or occasion of a law; the occasion of making a law. Bl. Law Tracts, 3. Ratio est formalis causa consuetndi nis. Reason is the formal cause of custom. Ratio est legis anima; mutata legis ratione mutatur et lex. 7 Coke, 7. Reason is the soul of law; the reason of law being changed, the law is also changed. Ratio est radius divini lnminis. Co. Litt 232. Reason is a ray of the divine light Ratio et anctoritas, duo clarissima mundi lamina. 4 Inst. 320. Reason and authority, the two brightest lights of the world. Ratio legis est anima legis. Jenk. Cent 45. The reason of law is the soul of law. Ratio potest allegari denciente lege; sed ratio vera et legalis, et non appa rens. Co. Litt. 191. Reason may be alleged when law is defective; but it must be true and legal reason, and not merely apparent.