I grew up listening to rock-n-roll in all its forms -- form Chuck Berry to Jimi Hendrix to Black Sabbath to Iron Maiden to Metallica. And even on occasion, I enjoyed one band almost every god-fearing parent of the 1980's despised -- Slayer.
When I got to college and read in Plato's Republic about the kinds of music he would have in his ideal state, I'd already moved beyond rock-in-roll to listening mostly to God's favorite music, Blessed Silence. So I was open to what Plato said. I wasn't sure I agreed with his views of music, but then I came across something Peter Kreeft said in The Snakebite Letters -- namely, that whereas the ancients made too much of the affects of music, contemporary men and women don't think it has any affect on them (if you have this passage handy, please put it in the comments). This little comment did more to convince me that Plato was correct -- that music does indeed influence us in ways in which we are not aware. Though it might be an overstatement to say that the music of Bach and Mozart raises us to the realm of angles whereas the music of Ozzy and Green Day bring us crawling on all fours, raving mad, like Nebuchadrezzar, it's not an overstatement to say that classical music brings tranquility to the soul whereas and rock-n-roll excites it.
How is this possible? How does rock music have such power? The gentleman over at Just Thomism wrote a post that explains rock's power. Here's an excerpt:
Beats move people in certain ways and so rock music seeks to move people in certain ways. We don’t mean motion in the sense of mere motion of the body--this is only a sign of an interior movement. The primary motion music causes is the motion of the affections, and since the affections are per se the seat of moral virtue, rock music has a per se effect on the seat of moral virtues an so also on morality. The lyrics are of relatively little importance--they need not be understood or even make sense. The moral effect of music will be much the same regardless of whether one sings about angels or demons. In rock music, the affections move primarily to the beat.The whole post is worth reading, but the sentence I highlighted in this excerpt is the key to the argument. If I understand St. Thomas correctly, the affections are what cause us to desire things, and our desires are important because we can only desire that which we believe to be a good. What we desire may not in fact be a good in the objective sense, but if we desire it, we believe that it is good for us at that moment. Thus, the whole rationale behind mortification is bringing right order to our affections. We all know from experience that it is easier to make a decision in a moment of tranquility than in a moment of excitement, but if our affections are aroused to excitement and disorder by rock music, how it is possible to make a good moral decision?