Out thinking is shaped by formal structures which are culture-based. Any intercultural communication which does not try to reflect this conditioning is one-way traffic. One conception, thinking in linear development as compared to the conception of a matrix-structure is discussed; switching from the level of formal structures to the level of the various meanings expressed through these structures the notion of the "humanum" of all cultures finds a surprisingly simple solution: Man is part of nature as well as a cultural being. Cultural expressions differ from one society to another. The "humanum" belongs to man's nature-dimension: Reproduction is central to all cultures. (Illustrations have been chosen mainly from the history of Cambodian culture.) To compare cultures through the formal structure of a matrix (not to be confounded with procedures of empirical research) means looking upon other cultures as subjects and not as mere objects of various development strategies, the aim being "to act so as to treat all cultures as ends and never as means".