Thoughts are energy, and like all energy, attract similar energies unto themselves.
This is the principle of resonance. That which you think of has a corresponding resonance, or energy match, with many objects and circumstances. As the entire Universe is energy, including the matter that makes up this book, this principle applies to circumstances, material objects, and people. Your unique way of viewing the world will affect the way in which you experience it as well as affecting the things and people that manifest in your life. For example, if you consider money to be a great source of freedom and you feel very free to express yourself, free to be who you are, then you will automatically draw more money into your experience because there is a vibrational match between the object, in this case money, and what you think and believe.