1. A pattern recognition system comprising a. pattern input means adapted to read an input pattern and to convert it into quantized electrical video signals; b. a two-dimensional memory adapted to store therein said electrical video signals as an input pattern information; c. similarity detecting means adapted to detect the degree of similarity of said input pattern information with stored standard patterns of different categories; d. input pattern identification means adapted to establish one-to-one correspondence between said input pattern information and one of said standard patterns when the degree of similarity of said input pattern information to only one standard pattern is high, and also adapted to provide an input pattern enlargement signal when the degree of similarity of said input pattern information with at least two of said standard patterns is high; e. an input pattern information enlargement control means adapted to enlarge a selected part of said input pattern information stored in said two-dimensional memory in response to said input pattern enlargement signal from said identification means; and f. an auxiliary input pattern identification means adapted to extract selected features of said enlarged input pattern information so as to identify and establish a one-to-one correspondence between said enlarged input pattern information and only one of said plurality of standard patterns.