The requirement for close derivation of the conceptual structures underlying various Jewish laws, as a regular part of one's Torah study, is described by Maimonides as follows:[2] A person is obligated to divide his study time in three: one third should be devoted to the Written Law; one third to the Oral Law; and one third to understanding and conceptualizing the ultimate derivation of a concept from its roots, inferring one concept from another and comparing concepts, understanding [the Torah] based on the principles of Torah exegesis, until one appreciates the essence of those principles and how the prohibitions and the other decisions which one received according to the oral tradition can be derived using them....Other such sources include Pirkei Avot,[3] the Babylonian Talmud,[4] Rashi,[5] and Shneur Zalman of Liadi.
[6] In the narrower sense, pilpul refers to a method of conceptual extrapolation from texts in efforts to reconcile various texts or to explain fundamental differences of approach between various earlier authorities, which became popular in the late fifteenth and early sixteenth centuries: its founders are generally considered to be Jacob Pollak and Shalom Shachna.
[8] Judah Loew ben Bezalel (the Maharal), in a famous polemic against pilpul, wrote: It would be better to learn carpentry or another trade, or to sharpen the mind by playing chess.
Afterwards, if G‑d has graciously endowed a person with a capable intellectual potential and broad-minded thought processes, he may delve into a pilpul....
In the late eighteenth and nineteenth centuries, pilpul in this narrow sense was largely superseded by the analytic methods pioneered by the Lithuanian school, in particular the Brisker derech.