It is not possible to define every concept, thus in mathematics we are forced by the limitations of logic as well as to some extent language to refer to certain ideas as _primitive notions_ or _primitive concepts._ %%See section 0 of Fraleigh%% --- # Recommended reading A concrete introduction of this fact as it arises in set theory may be found in * [Fraleigh, J. B, Katz, V. J. _A First Course in Abstract Algebra_, Addison-Wesley, 2003](John%20B.%20Fraleigh,%20Victor%20J.%20Katz%20-%20A%20first%20course%20in%20abstract%20algebra%20(2003,%20Addison-Wesley).pdf) pg 1. Here the existence of primitive notions in mathematics is introduced in order to provide a grounding with which to understand the role of set theory in abstract algebra. This text is aimed at undergraduates studying mathematics. #MathematicalFoundations