Necessity and sufficiency
= Necessity and sufficiency
{wiki=Necessity_and_sufficiency}
In logic, mathematics, and philosophy, the concepts of necessity and sufficiency are used to describe relationships between statements, conditions, or events. \#\#\# Necessity A condition \\( A \\) is said to be **necessary** for another condition \\( B \\) if \\( B \\) cannot be true unless \\( A \\) is also true. In other words, if \\( B \\) is true, then \\( A \\) must be true as well.