What mathematically or physically assumes no size, is usually numbered zero. An interval with the distance zero, however, is called Prim, because the zero came quite late - after 1200 - from the Arab world to Europe.

Since then, musicians compare a single tone with itself and identify matches. They call this phenomenon consonance.

Test: Take a photograph of a chair 2 times from the same place and then compare the photos. Amazing: The backrest looks the same and the right leg has been damaged in exactly the same place. Conclusion: Whenever you compare something with itself, you will find something identical.

Now count to 8. In mathematics you are dealing with sizes and distances, in music with whole-tone and semitone steps. Five whole-tone steps and two semitone steps lead to the octave. In mathematics, you would need five wholes and six halves to arrive at the eight. That doesn't matter at the moment, because you will discover the reason.

The tone you hit on reaching the octave has the same letter name as the one you started with, because they are so akin to each other. The homonym is supposed to express similarity, as if they had no distance from each other and were in fact merged. It's like closing a circle by combining the beginning with the end.

Mathematically, the frequency of the first note has been doubled. Two is twice the one. That twice of the same thing is similar to each other, I do not have to explain again. And the similarity can not only be calculated, you can hear it - and you would taste it, if you eat 2x the same or twice as much. Are we again talking about consonance? Musicians do so and the listeners are delighted.

Now a theologian joins in and finds all this very amazing. The 1 (Prim, which is actually a zero) reminds him of the beginning of all things, the 8, (which would have to be a six) to the 8 blessings of the Sermon on the Mount (which, in turn, would have to be nine because the disciples were not count as if they did not deserve salvation, compare Matthew 5: 3-12). And everything is so perfect matching with the A and Ω - yes, certainly: just only not the counting method.

But maybe everything was the other way around: A theologian wanted to establish the connection with the Holy Scriptures and changed the natural sound series according to his worldview. In this way, the monk Guido of Arezzo (*992-†1050), but also some monks before him, could gain prestige with his superiors. It just always had to look like former generations would wanted to say the same before. This gives honor and meaning to the whole. Thanks to this mental chain reaction - the continuity of piety - we have a sound system tailor-made for theological needs. Every historical layer has its own references.

Guido of Arezzo and Bishop Theodaldo are discussing a monochord, Österreichische Nationalbibliothek, Musiksammlung, Vienna, Codex Lat. 51, fo35v, 12^th century

Now listen carefully: there is usable scholarship and useless scholarship. Even fake news are often taken up when they are strategically useful. The Donation of Constantine was e.g. very helpful for the church, although it was a forgery. The value of the truth is not appreciated if it can not be used to any advantage. There are also many uncomfortable truths. Nobody likes them. Anyone who strives for truth alone and thinks too little of himself, starts a journey of suffering.

The theologians were concerned with something important. They saw the parable in music, the model of thought, the didactic aid. They heard the consonance as much as they saw the light. They envisioned that a higher power - the creator of all things - exists beyond our sense perception - that it begins just past our most beautiful impressions - behind the light and the consonance - hoping that sometimes a little divinity would shimmer through - like the light through a church window. Theologians are not praying to the sun. Anyone who wants to describe something that cant' be shown directly has to resort to analogies (parables). Therefore, our cultural history is so filled with religious symbolism that sometimes you can not see the sky because of the amount of angels.

Let's take, for example, the weekdays. Earlier we started counting with Sunday, the day of the Lord (dies dominica). This is the only way to understand what Guido von Arezzo writes: "For as we begin again from the beginning after seven days, so we always designate the first and the eighth day as the same, and we designate and name the first and the eighth sound always with the same letter, because we feel that they are in natural harmony in tone, such as D and d." The connections within the Christian worldview can hardly better be described, and it goes without saying that they also played a role in the view of the cosmos, keyword: harmony of the spheres.

This has nothing to do with a scientific observation or an acoustic exploration of the natural tone series. The Guidonian division is therefore not a tuning but a theological dream in which it is possible to count up to the eighth of the seven existing days of the week - the first twice - and to reduce the number of eight chosen tones to seven by double naming - the same name for prime and octave. This is the only way to relate the two to one another. The only thing that counts is the idea of ​​a divine order in all things, according to Wisdom 11:21: "But you have ordered everything by measure, number and weight" and the congruence with John 22:13: "I am the Alpha and the Omega, the beginning and the end". Again, the significance of the number eight is remarkable; it stands for closeness to God and is associated with the sun, the Lord's Day and consonance. Although Guido of Arezzo refers to Pythagoras, he created something new and theologically founded that owes nothing to Greek prehistory. Therefore, the so-called Pythagorean tuning does not deserve its name, because Pythagoras (*around 570 BC - †510 BC) could not have known about the world view of Guido of Arezzo. The attribution of authorship was deliberately based on antiquity, which can even be shown in the case of Glarean (*1488-†1563).

Against this background, it is not surprising that the occurrence of the number 8 in liturgical chants can be perceived particularly intensely. The number has a magic that "borders on magic in the symbolic vision of the world," writes Giacomo Baroffio, a recognized expert on Gregorian chant, and laments the resulting melodic limitations in comparison to Arabic music.

And as if Guido of Arezzo wanted to introduce us to the way of thinking of his time, he does not forget to point out the occurrence of the number 8 in the 8 parts of speech, as the prologue to the Gospel of John 1:1 states: "In the beginning was the Word, and the Word was with God. This was in the beginning with God." We learn from this: around the year 1000, closeness to God is unconditionally associated with the number 8. Therefore even the figure eight (∞), used as a symbol of infinity, introduced by the mathematician and royal chaplain John Wallis (*1616-†1703), may still be traced back to the widespread symbolic reference. Further examples can be found in the presentation: VII "How the octave got its name".

On this page, Christian symbolism and the ethical content of Western harmony theory are recognized and presented in an appreciative manner for the first time after centuries of oblivion. Ethics is not about favoring one religious denomination, but simply about living together in a functioning way. That is why we speak of harmony between sounds and harmony between people. This harmony is not a given - it is rather a rarity. Many people, but especially those who suffer as a result of injustice, long for it - regardless of which culture they belong to.

Well, now you comprehend the meaning and don't have to wonder about an illogical sound system.

Musicology still believes that our sound system derives from the Greeks. However, they were able to count very well.