From the Kav HaMidah (The Measuring Line), which, in a person, is the slight extension from the Reshimu (Impression) of his soul, a general desire that includes his entire life is revealed. This general desire is his very identity. It defines who and what he is. This general desire is his Ratzon Kadoom (Primal Desire). This is to say that his natural tendencies and primal defining desires come into being. Hidden in these primal tendencies are all the desires he will have during his lifetime. For example, every person has the primal desire and need to understand and be understood, to love and be loved, to communicate etc. These primal desires include every subsequent desire that should ever arise during the course of his life. This is evidenced in the fact that a newborn squirrel is born with the natural tendency and primal urge to live in a hole in a tree and that he enjoys eating acorns etc. These are all defining characteristics of a squirrel. A human newborn, on the other hand, is born with the desire to live in a house and may grow up loving strawberry sundaes topped with chocolate fudge and whipped cream, all of which a squirrel would consider to be quite inedible. In the same way, since the Ratzon HaKadoom (The Primal Desire of Creation), is the desire for everything in existence. It defines all of existence and is its essential identity, so to speak.