The symphony is a musical epic. We might compare it to a journey leading through the boundless reaches of the external world, on and on, farther and farther. Variations also constitute a journey, but not through the external world. You recall Pascal's pensée about how man lives between the abyss of the infinitely large and the infinitely small. The journey of the variation form leads to that second infinity, the infinity of internal variety concealed in all things.

What Beethoven discovered in his variations was another space and another direction. In that sense they are a challenge to undertake the journey, another invitation au voyage.

The variation form is the form of maximum concentration. It enables the composer to limit himself to the matter at hand, to go straight to the heart of it. The subject matter is a theme, which often consists of no more than sixteen measures. Beethoven goes as deeply into those sixteen measures as if he had gone down a mine to the bowels of the earth.

The journey to the second infinity is no less adventurous than the journey of the epic... Man knows he finds it unbearable to be condemned to lose the second infinity as well, the one so close, so nearly within reach....

--from The Book of Laughter and Forgetting; Milan Kundera