The Law of Attraction is the most powerful law in the universe. Just like gravity, it is always in effect, always in motion. It is working in your life at this very moment. You are always in a state of creation. You are creating your reality in every moment of every day. You are creating your future with every single thought: either consciously or subconsciously. You can’t take a break from it and decide not to create because creation never stops.
Law of attraction practiced prior to the 1800s. If you are referring to arcane practices in Babylon and Biblical times that we have little knowledge of, I am aware and have looked at these. If there are some specific and relevant references I would be interested in hearing them. As you believe in a LOA, most of what you hear will be filtered through this lens. As I now do not, most of what I hear will be seen through that lens.
How Do Angels Manifest Themselves
You claim that "positive thoughts always resulting in positive things" is not the basis of the LOA. In part you are correct. The foundational basis in science, as I alluded to in the article was that thought stuff particles travel through ether (not air) and interact with formless stuff to create whatever it is that you are thinking about. This was how "the law" started.
How To Manifest What I Desire