The chart this position belongs to is presented to readers as one system with one pedigree, and it is not. It was assembled in the United States across roughly sixty years by several authors who did not all agree, and the sources for these positions name four of them between 1908 and 1965.
L. Dow Balliett published the letter-value chart and the earliest positions in 1908, out of New Thought material rather than out of anything Greek. Cheiro, whose real name was William John Warner, brought a rival letter table and a large popular audience in the 1920s. Florence Campbell and Juno Jordan added and systematised further positions in the decades after. The pinnacles, the challenges, the cycles and the personal year figures all arrived in this way, and so did the minor positions, which presuppose the major ones and therefore cannot be older than them.
That layering is the honest fact about the chart, and it is worth stating because the system is usually introduced with a claim about Pythagoras. There is no line of descent from the Pythagorean societies to any of this. The ancient arithmological literature is interested in what numbers are, in the classification of odd and even and perfect and triangular; it is not interested in what a number says about a person, and it has no letter table.
The Minor Soul Urge is therefore a twentieth-century refinement of a twentieth-century instrument. That is not a criticism of it. It is what it is.