Describing the Dictionary Searching Process

  1. Open the dictionary to some page.

  2. If the word is on that page, stop.

  3. Otherwise, determine which part of the dictionary, left or right of the current page, the word is in.

  4. Open that part of the dictionary (left or right) to some page.

  5. If the word is on that page, stop.

  6. Otherwise, determine which part of that part the word is in.

  7. Open that part of the dictionary ... etc.
Note that steps 1, 4, and 7 each specify the same action, only using a smaller part of the dictionary as their object.