One Form of Successive Approximation Method and Choice Problem
  A mathematical model of Subject behaviour choice is proposed. The background of the model is the concept of two preference relations determining Subject behaviour. These are an "internal" or subjective preference relation and an "external" or objective preference relation.   The first (internal) preference relation is defined by some partial order on a set of states of the Subject. The second (external) preference relation on the state set is defined by a mapping from the state set to another partially ordered set. The mapping will be called evaluation mapping (function).   We research the process of external preference maximization in a fashion that uses the external preference as little as possible. On the contrary, Subject may use the internal preference without any restriction.   The complexity of a maximization procedure depends on the disagreement between these preferences. To solve the problem we apply some kind of the successive approximations methods. In terms of evaluation mappings this method operates on a decomposition of the mapping into a superposition of several standard operations and "easy" mappings (see the details below). Obtained in such way superpositions are called approximating forms.   We construct several such forms and present two applications. One of them is concerned with a hypothetic origin of logic. The other application provides a new interpretation of the well known model of human choice by Lefebvre. The interpretation seems to suggest a justification different from the one proposed by Lefebvre himself. 
Valeriy K. Bulitko