कूर्माङ्गन्यायः
It originates from the fact that a tortoise projects its limbs, i.e., its legs and neck, when it has to serve any purpose, and again it draws them in, when that purpose is served, or any danger is apprehended. It is used to denote that a sensible person will like a tortoise make an exhibition of his power only when there is an opportunity or necessity for it.
