When Stevie Wonder applied his tremendous songwriting talents to the unsettled social morass that was the early '70s, he produced one of his greatest, most important works, a rich panoply of songs addressing drugs, spirituality, political ethics, the unnecessary perils of urban life, and what looked to be the failure of the '60s dream -- all set within a collection of charts as funky and catchy as any he'd written before. Two of the highlights, "Living for the City" and "Too High," make an especially deep impression thanks to Stevie's narrative talents; on the first, an eight-minute mini-epic, he brings a hard-scrabble Mississippi black youth to the city and illustrates, via a brilliant dramatic interlude, what lies in wait for innocents. (He also uses his variety of voice impersonations to stunning effect.) "Too High" is just as stunning, a cautionary tale about drugs driven by a dizzying chorus of scat vocals and a springing bassline. "Higher Ground," a funky follow-up to