From The Gnostics by Jacques Lacarriere:
These convictions (of material existence as an Error) were expressed through a radical teaching which held almost all the systems and religions of former times to be null and void. In spite of its links with some philosophies of the time, and apart from minor reservations-since they borrowed certain beliefs indiscriminately from various systems, prophets or sacred books-one can say that Gnosticism is a profoundly original thought, a mutant thought.
This rejection of all systems, and of a world governed not by men but by shadows or semblances of men - whom I will call pseudanthropes - forced them to live on the fringes of all established society, and to preach a refusal to compromise with false institutions, a refusal to procreate, to marry, to live in families, or to obey temporal powers, whether pagan or Christian.