Saxophone's first criterion is to see whether the subconscious mind "inhibits" or "lets go" the normal activities of muscles; The second criterion begins with the physiological differences of human gender and race caused by the basic mode of production. Although there are other factors leading to racial and physiological differences (such as climatic conditions and geographical conditions, etc.). ), although "pure physiological reality" will not be without the imprint of human primitive social organization, Sachs' choice of this starting point is undoubtedly very wise.