Lemma

A lemma is a proven statement or fact used as a stepping stone to prove larger, more complex theorems. Think of it as a helpful intermediary result that clarifies or simplifies parts of a proof process. Once established, a lemma can be reused in multiple proofs, saving effort and making the logical structure clearer. In essence, lemmas are building blocks in mathematical reasoning, providing foundational support so mathematicians can confidently develop and understand broader theorems.