Initially, individual elements stand out from reality. After that, a set are formed from some elements that have a common property. Shamans always know in advance how a set they want to show us.

I will show the process by example. We select "red solid with holes" - these are our elements. At the same time, we see that these elements are with a bow, and there are without a bow. After that, we select some of the elements and form a set of "with a bow." This is how shamans get their food, tying their set theory to reality.

Now let's take a “solid with holes with a bow” and combine these elements by color, selecting red ones. We got a set of red. Now the question is: the resulting sets "with a bow" and "red" - is it the same set or two different sets? Only shamans know the answer.

This simple example shows that set theory is completely useless when it comes to reality. What's the secret? We formed a set of "red solid with holes with a bow". The formation took place in four different units of measurement: color (red), strength (solid), integrity (with holes), jewelry (with a bow).

**Only a set of units of measurement allows us to adequately describe real objects in the language of mathematics.**Here is how it looks.

The formation of the set |

The letter "a" with different indices indicates different units of measurement. In brackets, the units of measurement that are considered at the preliminary stage are highlighted. The unit of measure by which the set is formed is the set out of brackets. The last line shows the final result - an element of the set. If we use units of measure to form a set, then the result does not depend on the order of our actions. And this is mathematics, and not the dancing of shamans with tambourines. Shamans can "intuitively" reach the same result, arguing for its "evidence", because units of measurement are not included in their "scientific" arsenal.

Using units of measure, it is very easy to split one set into several subsets, or to combine several sets into one set. Let's take a closer look at the algebra of this process.