2Pac recorded so urgently and continuously, and was so unpredictable, that his catalog can surprise years after his death. On the bluesy, fatalistic “Smile,” he urges you to keep your sense of humor through life's worst; on the warm, Brand Nubian-sampling “Old School,” he fondly recalls the hip-hop of his childhood. He could be militant (“Bury Me a G”) or conscious (“Words of Wisdom”), and he was still somehow always Pac.