The Merkaba (Tetrahedron/Star of David) is used by most traditions to graph what occurs when one source separates to understand itself, and to expand its abilities. It is the core geometric form in many sacred graphs, such as the Far East Mandalas and Yantras. The merkaba represents source examining itself – what it is and is not – the polarities that exist to hold energy in place. It is often used as the symbol for creation itself, and in some cases the central symbol for certain deities.
Proportions - The Eye of Horus was believed to have healing and protective power, and it was used as a protective amulet, and as a medical measuring device, using the mathematical proportions of the eye to determine the proportions of ingredients in medical preparations) to prepare medications. It's also where we get our Px prescription symbol from.