Without question, John Lennon gave us some of the most enduring music of the previous century, yet everything he wrote appears destined for perpetual scrutiny. He left behind a massive catalog of some of the finest songs the idiom has to offer -- the bulk of which are acutely personal in nature. For the first half of the 1970s, Lennon was the angry and, at times, self-righteous protestor of everything from the war in Vietnam to getting out of bed. Songs such as "Give Peace a Chance," "Power to the People" and "Working Class Hero" -- powerful slogans and scathing indictments in their day -- have lost much of their bite, primarily due to their disturbing and perverse use in ad campaigns, something that would surely make Lennon purple with rage. The remainder of his solo output has a tendency to be spotty, but there are certainly some unmatched heights, from his perennial rocker "Cold Turkey" and signature song "Instant Karma! (We All Shine On)" to the tonsil-shredding masterpiece "Mother" and his pure pop comeback "(Just Like) Starting Over." With his trademark reverb-heavy vocals, the unapologetic exposure of his beleaguered emotions, and a lifelong fascination with the Chuck Berry riffs that initially inspired him, John Lennon gladly offered the world ringside seats to the overhauling of his psyche and, for a time, acted as an outspoken, prickly conscience to us all. His unfathomable murder in 1980 remains one of the most mourned losses in the history of rock 'n' roll.