We're used to thinking of the 20th century as the high point of technological and cultural change. The case is easy to make: A generation which knew the horse and buggy watched Neil Armstrong's moon walk. There was Einstein, two world wars, a smallpox vaccine, Elvis Presley and laptop computers. Make your own list.
However, two and a half centuries ago, subtle dramas of ideas and aesthetics led to contemporary upheavals every bit as volcanic as our recent spectacles. They may seem small to us, but like Captain Picard's Spatial Anomaly, they were much bigger in the past.
It may take an act of the imagination to hear the danger in 18th century music today, but rules of proportion and procedure in a coherent world were often being trampled by young, and not so young, artists. These subversives were obviously bent on destroying the very fabric of society. Antennae were finely tuned among the elite classes to detect such things. After all, the stakes were real, and high. These breaches of decorum might lead to anything, and did: a loss of power, the rights of citizens, bewigged noblemen hogtied in tumbrels approaching guillotines. Wolfgang Mozart, among these agitators, wrote his Divertimento in D, K. 136 at age 16. We hear the charming and graceful prodigy announcing his genius — a familiar, even comforting sound. But rebellion lurks beneath the surface: This teenager is out to change things. He abruptly wrenches the complacent courtier from one key to another. And those clever turns of phrase, are they really quite polite? No doubt he was on a watch list.
Carl Philipp Emmanuel Bach was another disturber of the peace. Superbly trained by his father, this second son of Johann Sebastian had his own things to say. His style was expressive, even stormy, with no built-in impedance against the display of human emotions. His symphony in B minor, for instance, with its stabbing rhythms and dissonance, gives us a forward-thinking C.P.E. Bach in the year 1773.
Finally, consider Joseph Haydn's Violin Concerto in C. Another innovator, and inventor of lasting things, Haydn developed both the string quartet and the symphony. On the surface, his style in the Concerto says "Empress Maria Theresia," but the virtuosic solo part anticipates the untrammeled humanity of Beethoven and Brahms. These men — living through and after Reigns of Terror and the Napoleonic promise and betrayal — inherited Haydn's legacy of change and accelerated it as we fell into the 19th century super-volcano of storm- and science-tossed souls. Trains broke the 25 mph barrier by the 1830s. This was too much, and Cassandras in the press warned, "The end is near!" Our incessant tectonic shifts for more than a century — from slide rule to nanotechnology, from Kitty Hawk to the Mars Rover — have conspired at last to make our response to apocalyptic change relatively laconic. After absorbing the assaults of the last century and our adolescent 21st, we might wonder: Can we ever again know the original shock of Mozart's juvenilia, or a C.P.E. Bach symphony?