People living today have the same access to the original creators' texts online as people in 1880 had in printed books. It's exactly the same material. You're essentially arguing against yourself because asserting that no one knows for sure about it would have to apply to the people in 1880 as well. Your argument is an appeal to ignorance, which is a logical fallacy. The text in the creators' books is precisely the data he's referring to, a intellectual creation that has absolutely no scientific basis.
The Law of Attraction is a deep subject and you seem to only have a very superficial understanding of it paired with a closed mind. The reason most people aren't excellent at it is that most people have very deep seated beliefs about limits and have a lot of fearful thoughts that they pick up from society. Even babies pick up and mimic the negative moods of those around them.
Is there any truth to “The Secret”? Is there any validity to the law of attraction? As with most other popular ideas, “The Secret” has a nugget of truth that is expanded to unbiblical and illogical extremes. For example, a thesis of the law of attraction is that our physical health is determined by our thoughts and feelings. It has been medically proven that stress and worry are harmful to the body, while joy and peace actually aid in the healing process. The Bible agrees, “A cheerful heart is good medicine, but a crushed spirit dries up the bones” (Proverbs 17:22). “A cheerful look brings joy to the heart, and good news gives health to the bones” (Proverbs 15:30). As David was struggling with the guilt of his unconfessed, evil actions, he declared, “When I kept silent, my bones wasted away through my groaning all day long” (Psalm 32:3). Our thoughts and feelings do have an impact on our physical well-being. However, this is due to how God designed our bodies…not because of our connection with a universal energy force and our negativity or positivity attracting negative or positive physical symptoms.
Emmet Fox wrote about metaphysics and the power of prayer in essays and books. His teachings are founded in Christianity and bible stories. He cites Jesus Christ as being the greatest teacher of metaphysics who ever lived and explains that thoughts are our most important emanation, more important than what we say or what we do. In the books Power Through Constructive Thinking and Find and Use your Inner Power Fox speaks about "building the mental equivalent of what you want and to expunge those that you don't".
How is that one person is willing to do all that it takes to reach their goals, while another person gives in to silent resignation at the first sign of resistance? Why is one person willing to sacrifice nearly everything in order to live the life of their dreams, while others are too afraid to take the next step in fear of suffering through a catastrophic failure or embarrassment?