when Eve was tempted by the serpent she had no knowledge.
The serpent lied and said to her "You will not surely die" “..you will be like God" Gen. 3.-5 But as Eve knew nothing about lying she believed the serpent. She did not suspect the truth of its words because she knew nothing about doubt.
Adam and Eve knew nothing but good. They did not know evil. But when they ate of the tree they began to know it