DEUT1637 The Three Branches of Wisdom. Wisdom can be divided into three parts: (1) the science of created things, namely, natural science, which deals with the natural and accidental properties of material bodies; (2) mathematics, which includes arithmetic, geometry, astronomy, and music; (3) theology, which is the knowledge of God, may He be exalted, and the knowledge of His Torah as well as of other subjects understood by the intellect, such as the soul, the intellect, and the spiritual beings. These fields of study, with their various divisions, are gates -- opened for man by the Creator, may He be exalted -- through which one can come to understand the Torah and the world. Some of these sciences are more vital for understanding the Torah, whereas others are more vital for worldly uses. Those which are more vital for worldly matters are the lower science (natural science) and the intermediate science (mathematics). These two sciences teach [us] of all the secrets of this world, of its uses and benefits that we may gain from it, as well as the different skills and crafts which are necessary for meeting physical needs and for the acquisition of various worldly goods. But the field of study which is essential to the Torah is the most lofty of all sciences, namely, theology, and it is our duty to learn this wisdom, in order to understand and realize the Torah. To study it in order to attain worldly benefit, however, is forbidden, as stated by our Masters: “It was taught: ‘To love Hashem your God, to obey His voice, and to attach yourself to Him’ (Devarim 30:20) -- [this means] that a person should not say: ‘I will study so as to be called a scholar; I will learn so as to be called ‘Rabbi’; I will learn in order to be one of the authorities in the Academy.’ Rather, learn out of love, and in the end honor will come .... Carry out the words [of the Torah] for the sake of the deed [itself]; study them for their own sake, and do not make of them a crown to win fame with, or an axe to cut with (Nedarim 62a).