The more precise defintion of gnosticism is:

BASIC TENETS - The world and our bodies were created by an incompetent lesser God, but we contain a spark of divinity, and Jesus provided us with the knowledge to free it.

REQUIREMENTS - Followers had to have the time to pursue and incorporate this special knowledge. Literacy may also have helped.

APPEAL - Gnosticism explained the world's hardships and people's feelings of not belonging to it but at the same time assured them that redemption is within their power.

e.g. today, though not the same, this is similar to Scientology (we were created be evil aliens, and they say their cult is a replacement to psychology rather than a theology).