Arithmetic is being able to count up to twenty without taking off your shoes.
Ludwig von Beethoven had never mastered the elements of arithmetic beyond addition and subtraction. A thirteen-year-old boy whom he had befriended tried unsuccessfully to teach him simple multiplication and division.
The hardest arithmetic to master is that which enables us to count our blessings.
If scientific reasoning were limited to the logical processes of arithmetic, we should not get very far in our understanding of the physical world. One might as well attempt to grasp the game of poker entirely by the use of the mathematics of probability.