Square and compasses

The Square and Compasses (or, more correctly, a square and a set of compasses joined together) is the single most identifiable symbol of Freemasonry. Both the square and compasses are architect's tools and are used in Masonic ritual as emblems to teach symbolic lessons. Some Lodges and rituals explain these symbols as lessons in conduct: for example, Duncan's Masonic Monitor of 1866 explains them as: "The square, to square our actions; The compasses, to circumscribe and keep us within bounds with all mankind". However, as Freemasonry is non-dogmatic, there is no general interpretation for these symbols (or any Masonic symbol) that is used by Freemasonry as a whole.

In many English speaking countries the Square and Compasses are depicted with the letter "G" in the center. The letter has multiple meanings, representing different words depending on the context in which it is discussed. The most common is that the "G" stands for God, and is to remind Masons that God is at the center of Freemasonry. In this context it can also stand for Great Architect of the Universe (a non-denominational reference to God). In a different context, the letter stands for Geometry, described as being the "noblest of sciences", and "the basis upon which the superstructure of Freemasonry is erected."

The square and compasses has used as a symbol by several organisations, sometimes with additional symbols:

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