Time was when I was unknown. I am the unknown quantity in mathematics. I have been discovered, and I have been applied to practical uses. I am the unknown quantity in an equation. I am the mark that stands between the known and the unknown quantities in an algebraical calculation. I am the mark of distinction between things different in nature, but similar in quantity. I am the mark of separation between things unequal in amount, but similar in kind. I am the mark of separation between things unequal in time, but similar in quality. I am the mark of distinction between things unlike in nature, but similar in degree. I am the mark of distinction between things unlike in quality, but similar in quantity. I am the mark of distinction between things unlike in time, but similar in respect to the
