Gnosticism is a group of religious beliefs based metaphysical dualism and knowledge gained by personal religious experience. Gnosticism is mainly known because of its influence on early Christianity but it may pre-date it by hundreds of years. Because it was perceived as a threat to the Christian church, it was declared as heretical and died out by the 5th century C.E. However, it occasionally re-emerged: as Catharism between the 12th and 14th centuries, as well as modern reconstruction movements.
It is difficult to reconstruct the beliefs of the gnostics because they often reserved their doctrines to their own initiates. Also, much has been lost because of the suppression of the movement by mainstream Christianity. For that reason, their true beliefs are a matter of speculation.
Gnostics believed that everything was either matter or spirit (known as dualism). Matter was corrupted and evil, while spirit was pure, good and incorruptible.
The true God was removed from creation which was the creation of a lesser creator god known as the Demiurge. This belief would be compatible with the argument from poor design.