Who dictates what is moral or immoral? What makes good rewarding and bad evil? How do you affirm this to be true?
That's kinda the point of #8. No one
dictates morality, as morality is a personal issue. Now, this might lead some to incorrectly conclude that laws are meaningless. However, this is because many people make the mistake of believing that legally, and morality are interchangeable. They aren't. Laws are not designed as a set of morals so much as sets of agreed upon social structures to allow people to exist together in a society. This is why laws vary from culture to culture; because, those are the set of rules that culture agreed to abide by to get along.
As to "rewarding" good, and evil, if you're talking about what I think you are, that is a function of neurology, and, I would assume, evolution. If you think about most "good" acts, they are acts that encourage survival of the species. As such, the body, over time, developed an internal system to encourage positive behaviours. Now, this is only a theory, mind you, however the theory does seem to be supported by the fact that aberations do exist. Sociopaths, and other aberrations receive the serotonin "feel good" jolt from behaviours that are entirely different from the "norm". Now, bear in mind, this, again, offers an opportunity for misunderstanding. For many the term "aberration" carries with it a negative connotation. Such is not meant. Rather, it is only meant to imply a genetic, or evolutionary outlier.
As to "affirming" the truth, I refer to you points 1, and 2. There are, of course, thruths that cannot be 100% certain. At such times, it is more rational to attempt to understand what is the most likely to be true, and proceed from there.