All symbols and images originate from the depths of consciousness. They serve the purpose of revealing the deepest and most profound aspects of realities that cannot be explained by the restrictions of verbal liguistics. The symbols used in Reiki have been used by so many for so long that they've been strengthened to the point where they automatically heal and harmonize consciousness, physicality, and psycho-spiritual health and well-being. Remember, energy always follows intent. Reiki symbols manifest potentials for creation into physical reality because Reiki symbols are literally energetic tools for transformation. Reiki symbols bestow the Reiki healer access to the unlimited potentials of Light energies present and available throughout the Universe through the Universal Life Force.
During a Reiki session the Reiki healer and the Reiki receiver are conscious and aware of the inner and outer realms of Infinite energy - on some level. Psychoanalyst Carl Jung explained that symbology is the fundamental basis for infinite consciousness communication. For example, think of a business logo: every business has a logo which conveys a vibration and a feeling about their business just by looking at it. A single image elicits a litany of psychological connotations through the use of color, design, etc. This is how spiritual energy communication connects with your consciousness - it accesses the symbolic language you already understand in order to communicate with you directly; which inspires exploration to learn more about what you saw. Interestingly, one of the definition of Logos is: the Word of God, or principle of divine reason and creative order. Thus, Reiki symbols help you establish an intimate conversation with yourself, your biology, your consciousness, your Infinite nature and All That Is. Even if you don't understand something with your MentalMind, the infinite nature of your SoulMind certainly does.
Reiki works even if you don't believe in Reiki because Reiki is pure Divine Universal Light energy that already exists in the Universe. Reiki/Universal Life Force energy is like air: you don't see it but you need it to exist - even if you don't understand the molecular composition of air, it doesn't matter. Your body still breathes and knows how to utilize the air you take in to keep you alive. Universal Life Force Energy, which IS Reiki, always perfectly harmonizes all energies bringing them into balance in accord with DivineDesign and honoring the sacred nature of All that Is.