Whether you believe that I am primarily responsible for these being primary, or if you believe that I create the complexity to the highest form of Sovereignty, I AM important!

I AM notorious in ‘true’ Shakespeare literature, Some say it is I who designate the meaning of the true human nature.
I AM the unassuming riddle of folklore,
A common relative to the story of Goldilocks, Cinderella and many more.
It is when I bring real dimension to the cycle of life, That the meaning of one’s existence seems less contrite.

Of the fraction of what is abundantly you - that I AM!
I AM vigilant in nature, the firmament, I am universal.
Was it not I who made Pythagoras’ theorem a mathematical conundrum.
It is by me that physics, chemistry, and the arts find equilibrium.

Me, myself, I - he, she, them – we, they, us - If it’s not you or me then by who or what is the crowd determined?

Clue 1 - Its not a person, place or spirit.

love

The number 3

Based on the clues provided, it seems that you are referring to the concept of the "I" or the "self."

The "I" or the "self" is notorious in true Shakespeare literature and is said to designate the meaning of true human nature. It is also associated with riddles and folklore, being a common relative to stories such as Goldilocks and Cinderella.

Additionally, the "I" or the "self" brings real dimension to the cycle of life and gives meaning to one's existence. It is a universal and vigilant force in nature, influencing disciplines such as mathematics (e.g., Pythagoras' theorem), physics, chemistry, and the arts. Furthermore, the "I" or the "self" plays a role in determining the crowd or collective identity.

Therefore, based on the provided clues, it can be deduced that the answer is the concept of the "I" or the "self."