Here’s an interesting quote by William Walker Atkinson:

“A recent writer on the “Taming of Animals” expresses instinctive realization of Spiritedness among some of the higher animals as follows:”Put two male baboons in the same cage, and they will open their mouths, show all their teeth, and ‘blow’ at each other. But one of them, even though he may possess the uglier dentition, will blow with a difference, with an inward shakiness that marks him as the under dog at once. No test of battle is needed at all. It is the same with the big cats. Put two, or four, or a dozen lions together, and they also, probably without a single contest, will soon discover which one of them possesses the mettle of the master.

Thereafter he takes the choice of the meat; if he chooses, the rest shall not even begin to eat until he has finished; he goes first to the fresh pan of water. In short he is ‘king of the cage. ’Now, then, when a tamer goes into a den with a big cat that has taken a notion to act ‘funny,’ his attitude is almost exactly that of the ‘king beast’ above mentioned would be toward a subject rash and ill advised enough to challenge his kingship.”

You will notice in the above quotation, that the writer states clearly that it is not always the baboon with the fiercest tusks that is the master, neither does the “king lion” necessarily assert his dominion by winning a physical fight – it is something far more subtle than the physical – it is the manifestation of some soul quality of the animal.

And so it is with men, it is not always the biggest and strongest physically who rule -the ruler becomes so by reason of the mysterious soul quality which we call Spiritedness, and which men often call “nerve,” or “mettle,” or “sand.”

When two individuals come into contact with each other there is mental struggle – there may not be even a word uttered – and yet soul grapples with soul as the two pairs of eyes gaze into each other, and a subtle something in each engages and grapples with a subtle something in the other. It may be all over in a moment, but the conflict is settled for the time, and each of the mental combatants knows that he is victor or defeated, as the case may be. There may be no feeling of antagonism between the parties engaging, but nevertheless there seems to be an inward recognition on both sides that there is something between them always leads. And this leadership does not depend upon physical strength, intellectual attainment, or culture in the ordinary sense, but upon the manifestation and recognition of that subtle quality that we have called Spirit.

People unconsciously assert their recognition of quality in themselves and others, by their use of the term. We often hear of people “lacking spirit”; being “spiritless”; and of others having had “their spirit broken;” etc. The term is used in the sense of “mettle. “A “mettled” horse or man is “high-spirited,” according to the dictionaries; and the same authorities define “mettlesome” as “full of spirit,” so you see the term is used as we have employed it – but the explanation of the source of the “spiritedness” is not given.

Breeders of thoroughbred racing horses will tell you that a horse having “spirit” will run a gamer race and will often outdistance and out-wind a horse having higher physical characteristics, but less “spirit” or “class.” Horsemen insist that the possession of “spirit” in a horse is recognized by the other horses, who are effected by it and become discouraged and allow themselves to be beaten, although often they may be better racing machines, physically.

This spirit is a fundamental vital strength possessed by all living things in degrees – and it may be developed and strengthened in one’s self.”