Translation of Genesis 2:9
God Yahweh caused to sprout from the soil all trees desirable for looking to and good for food and the tree of life in the middle of the garden and the tree of knowledge of good and bad.
... and the tree of knowledge of good and purpose
... and the tree of knowledge of good and thought
The garden of Eden was pretty big as there was place for every good tree in it.
There was a tree of knowledge of good and bad. It is conceivable to suppose that there were other trees of knowledge in the garden of Eden: Suppose you eat a fruit and after this you know algebra, or quantum mechanics, or whatever.
It is possible that "good" and "bad" here should be interpreted as pleasure and distress.
Victor Porton supposes that "the tree of knowledge of good and bad" injected knowledge into the human brain of how this brain itself functions (what it counts good and what counts bad). This knowledge allowed the brain to trick itself effectively causing a short-circuit. This is somehow similar to giving a program the password for complete control of the computer, this way a program becomes able to destroy the normal functionality of the computer (as well as to destroy itself). More specifically, the brain starts to work for what it makes up to feel better instead of the proper purpose, thus being deceived by the pleasure or distress.
See also Fall of the man article.
It is questionable, why God has planted the tree of knowledge of good and bad.
Analyzing of information presented on this page is complete (even with spaces hypothesis). That is, all variants of translation were considered carefully. No warranty however, that nothing is missing.