The analysis of cognitive functions of dilemma are undertaken to show the substantial character of thinking and limits of its formalization in AI programs. Substantial features of complex dilemmas are considered, the concept “solution of dilemma” and “resolution of dilemma”, as well as the task of choosing between the dilemma alternatives are analyzed. It states that resolution of dilemma is a formal-logical algorithm of inference, provided by the axiomatic status of dilemmas; the solution of dilemma involves the disclosure the contradictions and searching for new relations between its terms and alternatives. This thesis is proved through the task taken from life experience of G.S. Altshuller (Russian inventor). Distinctive features of moral dilemmas formalization and the meaning of non-logical factors for its solution are discussed. The limitations of programming the morally qualified AI systems implemented in rigoristic ethics and natural law terms are shown.

Keywords: dilemma, contradiction, Artificial Intelligence, thinking