In the past, the arts and crafts' teaching was a property of separate social classes, depositories of ancient traditions, who devoted themselves to the secret studies of holy and symbolic architecture.
The most ancient signs that we know as far as the craft of stone-cutter is concerned have been found in Egypt and they date back to 2.200 years before Christ.
The stone cutters, since the ancient times, were used to mark their works. Those signs have been found in the ancient Egypt , in Mesopotamia, on the walls of Jerusalem, of Troy, of Olympia and of the ancient Rome, as well as in the Gothic, Romanic, Byzantine, Roman, Greek and Renaissance marks.
In the Ordinance of Torgau in 1462 you can find seven articles concerning the marks.
Even in another document, the Rule B in 1563 (Art.59) you can find these signs. As specified in these texts, the marks of the stone cutters answered to the signs of the belonging to the order. They were given during the solemn ceremonies, they were chosen by the masters and they can't be refused to a "honest" craftsman; moreover they should not undertake changes, and they should not be given to third parties, but they had to be kept as honorary signs.
If we try to observe and understand the stone language, we will realize that these signs are full of meaning and of a deep symbolism forgiven for some time.
Over the years the marks evolved, and they have been influenced by rituals and by religious, symbolic and effective aspects of the guilds, from the periods of transition among the various styles of building. The geometric differences of the marks of the stone-cutters denote the passage from an artistic age to another one.
The stone-cutters, had a particular and mysterious way to communicate: their teachings were transmitted orally, the word games were used during the special occasions, they were used to wear in a strange way, they looked at one selves, they put their feet, walked, greeted, thanked, drank and they offered their hand to the brother in a strange way. Their symbolic interpretation was linked to the tradition. The use of symbolism as far as numbers and tools are concerned has displayed a deep knowledge of the main principles of the architecture: the compass which draws the circle and divides proportionally, the square at right angles, the plumb-line which draws the vertical. The use of the circle, of the square, of the triangle and of other geometric figures was very important in order to build Romanic and Gothic monuments.