The word "I" is one of the shortest words in the English language; however, it carries the most meaning of all of our words. Think of the meaning behind it. It can be used to simply refer to oneself, sure, but it can also mean your TRUE self, the full compilation of all of the factors that make you up as a person.
The complexity of the word "I" suggests it is the MOST important word in our culture, and possibly all humans in existence. Do we ever really use it as a personal pronoun only? Some examples: "I think," "I can," "I will."
"I think": This conveys the fact that "I" has conceived of something; that is, something new has been incorporated into "I."
"I can": This says that "I" has the ability to do something; in other words, it is a possibility that some action can be incorporated into "I."
"I will": When a person says this, what it means is that the subject action has already been incorporated into "I," and will come into fruition at a future time.
All personal pronouns referring to other people are really referring to the "I" as it pertains to the subject.
Don't you love "I"? I sure do. (