For an arbitrary class of rings M, we have studied, in this paper, some necessary and sufficient conditions for ψM to be closed under homomorphic images or essential extensions, or to be a semisimple class or heredit...
A Class of rings is said to be weakly hereditary if 0≠I△R∈ implies 0≠I^n∈ for some positive integer n, which generalizes the concept of heredity but other than that of regularity. In §2 the properties of such c...