1. A learning and recognition machine, comprising: a major classification section for calculating a group belongingness which indicates a degree of how close an input pattern signal belongs to a category group composed of a set of similar categories, a plurality of fine classification sections each having an in-group similarity calculating section for calculating an in-group similarity which indicates a degree of how close said input pattern signal belongs to a category in each category group and a weight factor updating section for updating weight factors of said in-group similarity calculating section; a discrimination signal loading section for weighting each said in-group similarity by the group belongingness; a category discriminating section for comparing the weighted in-group similarities output from said discrimination signal loading section; a teacher signal generating section for generating a teacher signal output necessary for learning; a learning control section for outputting a learning control signal for controlling weights of each said in-group similarity calculating section based on the teacher signal output from said teacher signal generating section and based on the output of said discrimination signal loading section or of said category discriminating section; and a learning control signal loading section for weighting the learning control signal output from said learning control section by the group belongingness output from said major classification section; and each said weight factor updating section for updating the weight factor of each of said in-group similarity calculating sections being based on the outputs of said learning control signal loading section and of each said in-group similarity calculating section.