It is well known among the learned rabbis that G-d gave humans the ability to choose between good and evil, but not to determine what good and evil are.
In other words: each human being is able to make choices which are good, and which are bad, but it is not given to humans to determine their own tables of morality.
Now I am perhaps simply perverse and froward, but this seems to me a total opposite of reality. Humankind has, in its diverse cultures, been determining what is good and what is bad for as long as recorded history. Today in China, it is okay to eat dogs; in India it is not okay to eat cows; etc. But does an individual have the ability to choose between good and evil?
I personally suffer from very heavy bouts of depression, in which I am unable to concentrate on anything, so I cannot study or read or make conversation. It is not a conscious choice to avoid those things, but rather it is some profound evil which washes over me, as it were, some demon which has possessed me, and caused me to become such an abomination.
There are demons every which way, in the air, in the water. Sometimes a demon enters inside one after drinking coffee, and produces a pounding headache. But often I am simply overwhelmed by the demons around me, and I collapse, and as it were, become like a one possessed.
Here you might interject and point out that my weak constitution is as a result of my being a doctrinal heretic and a perverted soul. I have chosen evil, and I suffer evil consequences. But yet the question remains, whence came such a soul so predisposed to what is wrong? The simple fact remains that what G-d has given me is awful, and I can no longer off Him thanks for it, because I know not how to use it.
There is neither good nor evil - simply, necessity.