| first-order theory [¦fǝrst ´ȯrd·ǝr `thē·ǝ·rē] MATHEMATICS A logical theory in which predicates are not allowed to have other functions or predicates as arguments and in which predicate quantifiers and function quantifiers are not permitted. OPTICS See <<Gaussian optics>> PHYSICS A theory which takes into account only the most important terms, such as the term proportional to the independent variable in the series expansion of a function appearing in the theory. |