The Science of Mind, by Ernest Shurtleff Holmes , at sacred-texts.com
The most important thing that any student of the Truth can understand is the real meaning of self-existence. Whatever the nature of First Cause is, It must be Self-Existent, or else It could not be at all. It is, perhaps, hard to comprehend that there must be, and is, a Power which exists simply because It
is what It Is; and yet this is the mainspring of all right metaphysical work and endeavor.
We must come to believe in, and trust, that Power of Life and Intelligence which is God, or First Cause. We must understand that we deal with First Cause whenever we think, at any, and at all, times. If we had to gather energy with which to energize the Creative Principle of Life, where should we go to get the energy with which to energize It?
We are constantly thrown back upon the fundamental proposition that Life already Is; and that we use a Power which already Is. Let us then, without doubt or fear, throw our word into that Great Receptivity and trust It to do the work.