Paradox in ideals

All the teachings and preachings that I have read or heard have had some basic ideals, some bona fide concepts, some unquestionable axioms. I read about Nihilism today and it has left me befuddled. The concept of nihilism as defined by people far smarter than me is "Complete denial of all established authority and institutions." Is it something that we really want? As humans we have always wanted change but what would happen if Nihilism gains as the dominant philosphy in the world ? If there is no authority, no rules, no power position holders, what would we change? Ideals are supposed to be devoid of paradoxes but is that the case with Nihilism? If we accept Nihilism as an authority then how can we deny the existence of any authority. Hence just saying that "I am a nihilist." is no lesser a paradox than saying "I am a liar." On the other hand the concept has existed from the times of Demosthenes (c.371-322 BC) and is more than relevant in today's scenario. We are a generation that is raised more by TV commercials than by parents. We are used to things that make an impact on us in 30 seconds. We do not want to hold our thoughts for a long time. Nihilism is a constuct that we want, we need and should I say we deserve. It suits our 30 second mentality. I have said "I am a liar" in the past and so I feel no shame in saying "I am a nihilist" at this point of time, but not to forget that even this can fall prey to the hands of the animal we all call CHANGE.