Portrait of Euclid according to an old European etching

There are so many symbols, words and phrases in Freemasonry used both as part of its rituals as well as part of its vocabulary, that studying and trying to understand the “meanings” them is a very worthwhile and a rewarding journey. One such prominent symbol and phrase, is the 47^th problem of Euclid, which is one of the main symbols introduced in the Third Degree.

In the Blue Lodge, it is considered a great honor to be elected and serve as the Master of a lodge. It shows that the individual has attained maturity, leadership, charisma, and motivation, but above all, knowledge to be able to lead others. It is an initiation by itself, as the position brings with it a completely new set of responsibilities that are often not appreciated when accepting the position. At the end of serving as Master of a Lodge, many Past Masters are presented with a jewel, symbolizing the great appreciation of the Lodge towards their dedication. It also symbolizes something else ? that is that the individual has completed his “journey”, through the different positions of the Lodge, to a new plain.

The 47^th problem of Euclid features prominently in many Past Master’s jewels. Selecting this symbol out of the thousands used in Freemasonry to represent one of its highest honors must mean that it is a very significant and central symbol of the Craft. Yet, sadly many Freemasons, even many Past Masters, do not know why it is so centrally featured in the Past Master’s jewel. Clearly the 47^th problem is based on Geometry, and all Freemasons know that Geometry and Freemasonry are closely linked, but is this the only reason? What does the 47^th problem of Euclid symbolize and mean? Of the 465 problems published by Euclid, why is the 47^th so important? Why do Freemasons cherish it so?

(An example of a Past Master’s Jewel featuring the 47^th Problem of Euclid from England. Past Master’s jewel used in the USA often do not show the 47^th Problem anymore)

The 47^th problem of Euclid is often mentioned in Masonic publications. In Anderson's “Constitutions” published in 1723, it mentions that “The Greater Pythagoras, provided the Author of the 47th Proposition of Euclid's first Book, which, if duly observed, is the Foundation of all Masonry, sacred, civil, and military…”. Being mentioned in one of the first “official” speculative Masonic publications clearly indicates that the 47^th problem of Euclid must be important. It is also mentioned in the Third Degree lecture, where we are taught that the “47^TH problem of Euclid…….taught us to be general lovers of the arts and sciences”.

However, it is quite different to be referred to as the “Foundation of all Masonry, sacred, civil and military” that to be referred to as “taught us to be general lovers of the arts and sciences”. Has the importance of the symbolism of the 47^th problem declined over time for some reason?

Euclid wrote a set of thirteen books, which were called “Elements”. Each book contained many geometric propositions and explanations, and in total Euclid published 465 problems. The 47^th problem was set out in Book 1, which is also known as “The Pythagorean Theorem”. Why is it called by both these names? Although Euclid published the proposition, it was Pythagoras who discovered it. We learn from the third degree lecture that:

History records that Pythagoras established a society with philosophical, religious and political aims. Shrouded in secrecy, they believed that only by truly understanding the universe could one achieve salvation of the soul, and as Divinity created all things, studying it over a period of several lifetimes, could bring one closer to Divinity itself. As such, it was believed that through study and reason could one start to understand Divinity. Clearly, reason is based on measurable things (such as through numbers and objects), and is easier to understand if expressed in that matter. Hence the society devoted much of its time to the mathematics, including Geometry. This line of thinking was incorporated in Freemasonry, which sets it opposite to the Church, which emphasizes faith over reason. Indeed, Pope Pius IX, in his encyclical, Qui Pluribus, dated 9 November 1846, attacked those who “put human reason above faith, and who believe in human progress.” Many people consider this to be a reference to Freemasonry.

“Even apart from these, men could fall at a single breath
when pursued by justice
and scattered by the breath of thy power.
But thou hast arranged all things by measure
and number and weight.”

So the very “measurement of things” the Church objects to is mentioned in Scripture.

The proposition states that: “In right angled triangles the square on the side subtending the right angle is equal to the squares on the sides containing the right angle.”

What? In other words A2 + B2 = C2.

The proposition is especially important in architecture. Builders have since ancient times used the theorem in constructing buildings by a process known as “squaring a room.” As the theorem states that 3 squared + 4 squared = 5 squared, a builder starts by marking a spot and drawing a line, say line A. This line is given the value of 3. The builder then marks another point, say point B and draws a line from it at a right angle to line A, and it is given the value of 4. The distance between line A and B is then measured, and if the distance between A and B is 5, then the room is squared. By inverting the process, a “squared” (or rectangle) room can be obtained.

In some lodges, using this principle, a candidate symbolically “squares the Lodge” by being escorted around the Lodge three times during the Entered Apprentice ritual, four times for a Fellowcraft ritual, and five times for a Master Mason ritual, which completed his journey.

Please see the illustration above, which is not accurate due to a drawing, but will serve to illustrate the point. If we take a circle and draw in it a triangle (triangle A- B-C) which perpendicular is 300, base is 400, and by the 47^th problem, the hypotenuse becomes 500 (any combination such as 3,4,5 will also work ? higher numbers are used for ease of explanation). Then if we draw a line from the angle of the perpendicular and the base through the hypotenuse to the circle, this line will be equal to 480. The

Clearly, the 47^th problem helps us look at the universe, and all that is in it, through a system that we can understand clearly, for it is measurable. The Master’s jewel is the square, the base needed for the 47^th problem (in many jurisdictions the square has the dimensions of 3:4 ? the Pythagorean dimensions). As the Master serves his position, he becomes more complete, and therefore the 47^th problem of Euclid is dedicated on his jewel when he leaves office.

Circumambulation and Euclid’s 47^th proposition, by Reid McInvale

Return to Masonic Papers

Return to Main Page