Before I start, I will define power: ability to do or act; capability of doing or accomplishing something.

From the Antichrist. Section 2.

What is Good? All that enhances Power. What is Bad? All that proceeds from weakness. What is happiness? The feeling that Power is increasing, that resistance has been overcome.
Is Neitzches theory correct?

Looking at it secularly (as I need all others involved to do), he seems to be correct. Life is centered around power, ability, and accomplishment. The fittest are always the most powerful. Those whith the most power reproduce, that is natural selection.

Power is the cornerstone of life (Neitzche theorizes so). All that enhances your power, which in turn continues your existence and importance, is good. (Is he right?)

All that is bad is something that demerits, demeans, and decreases your power, and thus your importance and degrades your existence, is bad. (Is he right?)

All that is happiness derives from the increasing of power, and the decrease of opposition. (Is he right?)

I think hes right......even though he was a tad bit insane at the time of his writings.....