Gratitude is a cornerstone in the process of manifesting. The vibratory energy of gratefulness causes physical reality to produce more things which resonate with the gratefulness you are feeling, thus causing an even more powerful feeling of gratefulness. It keeps building and building, multiplying exponentially. The more grateful you are, the more physical reality responds to this by sending things which match the vibration. The more intensely gratefulness is felt, the more quickly physical reality responds.