To take some simple examples, the simple patterns on the next page are a small subset of the patterns used to make up printed letters. Note that every level constitutes a pattern. In this case, the shapes are patterns, the letters are patterns, and the words are also patterns. Each of these patterns has a set of inputs, a process of pattern recognition (based on the inputs that take place in the module), and an output (which feeds to the next higher level of pattern recognizer).
