This is a rather persistent theme in my work, so it bears repeating here: if you want to elevate your life and become a manifester, then you have to change what you’ve believed to be true about yourself that has landed you where you are. The sentiments of This is reality, This is just the way things are, There is nothing that I can do to change what is, and the like are pernicious thoughts that will taint and defile your great gift of I am that I am, which is your Divine inheritance from your creator.
It will signpost the way for you to achieve your goals in the best possible fashion. Your awareness will expand to include all the ways in which you can move towards your dreams. You'll be surfing the net and an ad will pop out at you, or you'll be walking down the street and be compelled to turn your head and hey presto - something that will lead you to your dream.
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.
Here is the most effective way. First of all, go onto google, print off all the images of your goals completed such as a 'six pack' 'mansion' and 'own business' etc. print them, stick them somewhere you will see them often. I put mine in a notebook alongside inspirational messages. Look at the images often, the subconscious will take note BUT will not yet be impressed with the information.
It all begins with putting the right messages out there into the world. Lots of people think that creating a vision board is enough, or trying to hustle to make things happen is the answer. The reality is, that manifesting something is a subtle energy. It’s about assuming the experience of what it is you desire before the reality even comes into form.