Art concerned with subject and content produced during the early 20th century was often overshadowed by Abstract Expressionism as the artistic mainstream of that time. Unperturbed by the trend, George Tooker (1920-2011) maintained a lifelong adherence to the use and ingenious techniques of tempera, and generated mysterious works that confuse yet intrigue the viewers.By collecting, translating, analyzing, contrasting and studying historical documents, and summarizing and commenting with methods spanning from psychoanalysis, aesthetics, art philosophy, art sociology to art criticism, the essay intends to investigate how Tooker reflected his views of reality, revealed the contradictions and complexities of humanity, induced a re-examination of the relationships between human and human, and human the environment, demonstrated a critical, dialectic thinking, and articulated his humanism and social concern by means of simulation and mirror images of reality.The research and analysis will provide us with a glimpse of how the artist captured in paintings the anxiety of the American crowd and social vicissitudes in the turbulence of the 20th century. Meanwhile, his attitude, spirit, and cultivation have inspired us to probe deeply into the essence of creation and humanism that are the due concern of contemporary art, and go beyond the confines of 'harmony' and 'beauty' that have circumscribed art practices and appreciation, and the shallowness of 'surface description' or 'faithful representation.'After a survey of the documents in various fields on the psychology and spirit of Tooker's oeuvre in Introduction, Chapter II of the essay proceeds to examine the four periods of his career chronologically from political, economic, cultural, social, religious, and emotional perspectives, and Chapter III offers an analysis of the characteristics of Tooker's work, before a conclusion is reached in Chapter IV.