IS IT A SIN TO RECOGNIZE GOOD AND EVIL?

Genesis 2:17  But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die. (KJV) Hebrews 5:14  But strong meat belongeth to them that are of full age, even those who by reason of use have their senses exercised to discern both good and evil. (KJV)

Since Adam and Eve ate of the tree of the knowledge of good and evil, we need to now recognize which is which.  To call this a contradiction would be like saying 'don't go into a snake pit' and saying 'now that you've fallen into a snake pit, you'd better figure out which snakes are poisonous and which are not' is a contradiction.  There is no contradiction.