Why do pure math?

• From a speech by Frau Bundesrätin Ruth Dreifuss to the International Congress of Mathematicians in 2002:

  "Pure mathematics seems to function within a realm of complete independence. Its results have their purpose not in their usefulness to society, but in their truth. The clarity of this truth finds a beauty which elevates pure mathematics to an art form. But, in contrast to a harpist who delights others by her music, I fear that the pure mathematician cannot make his art accessible to a wider public."

  She asks three questions of some eminent mathematicians, the first of which is "How can pure mathematics justify its art to the State who finances it?"