Agnosticism
Agnosticism was first used by Thomas Henry Huxley defining it as the view or belief that the existence of God, of the divine or the supernatural is unknown or unknowable.The view that “human reason is incapable of providing sufficient rational grounds to justify either the belief that God exists or the belief that God does not exist.”

According to Huxley , Agnosticism, in fact, is not a creed, but a method, the essence of which lies in the rigorous application of a single principle … Positively, the principle may be expressed: In matters of the intellect. Follow your reason as far as it will take you, without regard to any other consideration. And negatively: In matters of the intellect do not pretend that conclusions are certain which are not demonstrated or demonstrable.(source)
Agnosticism is a philosophy that rejects all claims of spiritual or mystical knowledge.
Gnosticism
Gnosticism is a collection of religious ideas and systems that coalesced in the late 1st century AD among Jewish and early Christian sects. These various groups emphasized personal spiritual knowledge above the orthodox teachings, traditions, and authority of religious institutions.
The origins of Gnosticism are not clear and still disputed. However, proto-orthodox Christian groups called Gnostics a heresy of Christianity
Gnostics considered material existence flawed or evil, and held the principal element of salvation to be direct knowledge of the hidden divinity, attained via mystical or esoteric insight. Many Gnostic texts deal not in concepts of sin and repentance, but with illusion and enlightenmen
Gnostic writings flourished among certain Christian groups in the Mediterranean world around the second century, when the Fathers of the early Church denounced them as heresy
In Christianity, Christ is seen as a divine being which has taken human form in order to lead humanity back to recognition of its own divine nature.
Efforts to destroy these gnostic texts proved largely successful, resulting in the survival of very little writing by Gnostic theologians. Nonetheless, early Gnostic teachers such as Valentinus saw their beliefs as aligned with Christianity. So In the Gnostic Christian tradition,However, Gnosticism is not a single standardized system.
Gnostic ideas spread as far as China and might have influenced other religions within the region.
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