La estructura lógica de la teoría clásica de las finanzas

in the present paper classical financial theory (tf) is presented in a complete, rigorous and compact way. it does not intend to introduce novel theorems, but only to interweave them using a method that has never been used in the demonstration of utility representations: tarski's (1957) theorem on fixed points of lattices. it defines explicitly the typical concepts applied in financial theory and practice, starting with the philosophically fundamental notion of rationality: the concept of preference. the contribution of the paper consists of presenting the fundamental concepts and theorems in a compact, orderly, rigorous and abstract way, as well as in providing novel proofs of the latter. the paper ends by offering a general explanation of the well-known concept of portfolio, taking advantage of the preceding abstract development. hopefully, this work will be useful in the teaching of tf.