
Fight Club organizes the transformation of the narrator from a white-collar wage slave into the leader of an anti-capitalist terrorist organization. His transformation, which involves rediscovering primal masculinity, is wrought through his identification with alter-ego Tyler Durgan, expertly played as the long lost rebel by Brad Pitt. In Fight Club, Pitt is literally the phallus, the film's image of male power. It becomes exceedingly clear that the narrator desires this stylized phallic image to combat the emasculation dealt out in daily life.
Ref. https://www.popmatters.com/film/fight-club.html
The character of Tyler Durden idealized the person that the Narrator, whom I will refer to as Jack, detested the most, but secretly wanted to emulate. This innermost want is what allowed Tyler to manifest unbeknownst to Jack. The sociological impact of the Tyler Durden character is to show that each one of us has an innermost person that we really know and believe is not who we would like to be, but through environmental pressures and strains, and lack of self confidence, possibly, we nurture and feed within ourselves. I think this is what appealed to me the most about Tyler was his lack of inhibition, and total freedom, a trait that Jack had to suppress because of his line of work. What were your reactions to the Tyler Durden character? What do you think he symbolizes?
I usually do not like Brad Pitt because he tends to exaggerate his characters to the extreme which makes them unrealistic. But in this movie, I liked him, because it was needed for Tyler to be unrealistic, since he was the result of Jack's wildest dreams and wishes. I also liked how the two complemented eachother and formed a whole.
I completely understand where you are coming from Smudge, as I too have never really cared much for his pretty-boy characters. Many have said this was his real shot at taking on the bad-boy image instead, but at a thespian level, and to be honest, I think he did a good job in pulling it off.
I agree with all the reviews for this character and will add that we are merely watching an ordinary man who has somehow suffered a nervous break down or serious depression to the point that he begins to be 'bored' with his way of life. You will recall that this began on the plane with the very first statement... "We have the same briefcase" to which Tyler seems uninterested. It seems that the Narrator by that point lost it because of insomnia, bad health, overdrawn credit, depression and routine in a dull life all rolled up into one.