The Chicago school of economics is an approach to economics started by a group of American liberal economists in the 1930s. The most prominent members of this group were Frank Knight, Henry C. Simons, and Jacob Viner. After the WW II economists like Milton Friedman, George Stigler, James Buchanan, and Gary Becker become the most recognized economist of the Chicago school.  The Chicago school of economics is notable for its ultimate trust in the power of the market and its forces in solving most economic problems. Members of this approach believe in the minimal state and minimal or no regulations of the economic sphere and the market. The third characteristic belief of this school is that humans are rational agents that are constantly trying to maximize their personal advantages.

References:

Becker, Gary Human Capital Theories. (1964); 

Friedman, M. and Friedman, R.D. Capitalism and Freedom. (1962);

Patinkin, D. Essay on and in the Chicago Tradition (1981);

Reder, M.W. „Chicago Economics: Permanence and Change”, in Journal of Economic Literature (1982);

Simon, H.C. Economic Policy for a Free Society (1948);

Stigler, G.J. (ed.) Chicago Studies in Political Economy (1988).