Happiness doesn't exist; there is simply the absence of unhappiness. (...) Looking back, you're right, it's all just word games. Playing with definitions.

This might be just another definition among many, but I think it is worth to look at the details. Emotions happen when some chemicals are released into our blood system.

So I could translate "happiness is simply the absence of unhappiness" as: there are chemicals people release when they are unhappy, but there are no specific chemicals for happiness; the feeling of happiness is the feeling of not having those unhappiness chemicals in our bloodstream. This would be a testable prediction. I am not 100% sure about biology, but I guess it would be false.

In which case we could try more generous interpretation, such as: Yes, there are specific chemicals for happiness, but they are released to the bloodstream automatically in the absense of the unhappiness chemicals. Again, a testable prediction. Again, I think even this would be false.

Your mistake is thinking that once you understand a thought is useless or wrong, it will go away. It won't, at least not for me.

I didn't mean to imply this. Useless thoughts don't go away just by realization they are useless; they are preserved by the power of habit.

Anyway, I was not sure if my reply wasn't too aggressive, so I am happy you reacted this way.