This chapter starts its point of departure from two problems that regularly recur in historical accounts of rock music. One historical thread that can be traced almost all the way back to rock's earliest days in the mid-1950s is the theme of musical ambition - the idea that pop can aspire to be a 'better' or more sophisticated kind of music by employing techniques and approaches often borrowed from other styles to make pop more interesting and original. The first and most dominant characteristic of the hippie aesthetic is the tendency to imbue rock with a sense of seriousness of purpose. From a musical point of view, this often took the form of borrowing from styles that had a high degree of cultural prestige, such as classical music and jazz. Hippie rock also borrowed from folk and blues styles, but drawing on these styles gave the music a sense of earthy groundedness that can often balance the music's higher aspirations.