I have always been infatuated with it in its romanticized form (reality is something altogether different, and I'll get to that in a moment). In fiction, nobility is often something rare, powerful, and real: a trait that elevates one person above another, no matter their other qualities.We see its undefinable effects all the time: an aura, a charisma, a strange power over others. It always runs in the blood, passed down from ancestors who were either born with it or acquired it through great deeds.
From a modern perspective, I find the idea absurd - even grotesque. It was and remains a naked mechanism to preserve power in the hands of those who already have it. In the real world, of course, "nobility" (as it pertains to a bloodline) is just a word, completely devoid of real meaning. People "of noble blood" aren't smarter, braver, or better looking. Due to centuries of inbreeding, it is often just the opposite.
On the other hand, "Nobility"-with-a-capital-N is very real. I do not know the etymology of the word - I do not know if it originally applied to the falsely exalted social class or the justly exalted state of being. I do know that unlike a social class, true Nobility is not inherited, and does not exist independent of a person's actions. Indeed, true Nobility can only derive from a person's actions, and can be both gained and lost.
It was perhaps a sign of my maturing outlook when I noticed something odd about my revered idol, Tolkien. He seemingly considered nobility as something that could be passed through bloodline, rather than something only earned through action. The extended mythos of Middle Earth is rife with the concept that great deeds are most often performed by those who are somehow descended from noble blood. With some important exceptions, such as the hobbits (which comforts me: I know that Tolkien didn't really have such an outmoded mindset), most great deeds are done by those descended of kingly or otherwise noble lines. Even Bard the Bowman, who kills Smaug in The Hobbit, is descended from the Kings of Dale.
Furthermore, there is evidence that even misdeeds cannot make one "lose" that nobility. We see this in Gandalf's tale of the slow fall of Gondor (and Numenor before it, but I'll try and stick to the better-known parts for my non-Tolkienite readers). Gandalf states that the Kings of Gondor began to neglect the rule of their kingdom:
The old wisdom that was borne out of the West was forsaken. Kings made tombs more splendid than the houses of the living and counted the names of their descent dearer than the names of their sons. Childless lords sat in aged halls musing on heraldry or in high, cold towers asking questions of the stars. And so the people of Gondor fell into ruin. The line of Kings failed, the White Tree withered, and the rule of Gondor was given over to lesser men.(Quote pulled from the movie, but there was something almost identical in the book)
Despite the fact that the stewards of Gondor ruled well and wisely for a long time, they are "lesser men" because they don't have that noble (lower-case n) blood. And despite the fact that the Kings of Gondor fell into folly, they were still "greater men" because of an accident of birth. Actions don't matter, only blood.
It could be said that Tolkien actually meant all this as indicative of the fact that blood-inherited nobility is drivel, because his nobles so often do fall into folly (and some of his greatest heroes who happen to be descended from greatness also struggled through great adversity, such as Aragon, and could have "learned" his greatness through that). I certainly think that he saw beyond an inherent belief in the greatness of noble lines. However, I also think - perhaps because of his own life, being both British and from mid-upper class - that at least part of him bought into it. I see it too often in his writing - doers of great deeds traced back to other doers of great deeds.
This post has already gotten long, so I'll close with one last point and continue the matter some other time: This lineage deal isn't entirely empty, but it isn't primarily because of blood. Some things are inherited, but it is my belief that nurture is the more important half of nature vs. nurture. Greatness of many kinds can be taught, and learned, and it is obvious that the children of Noble people would absorb some of it by the example of their parents. However, the children still need to earn Nobility for themselves (and historically speaking, being brought up as spoiled, entitled little shitbags ruins the lessons).