Since the appearance of man on the surface of the earth, one can say that the essence of his history lies in the modifications he has gradually introduced into the landscape. Destruction, change and construction: these three elements showed themselves very early on in man's history and, with its development, have taken on an ever clearer and more marked character. If the action of a single man on the environment is already important, then that of a larger number can have modifying and absolutely determinative consequences.

The question whether western civilization as a whole constitutes a structured and coherent unit poses insoluble problems for any pure historiography. It is, however, a real problem for history, and in our day and age when this civilization is constantly in contact with the civilization of other continents, this question becomes daily more important. In what does the essential structure of the European universe reside? What, in relation to oriental civilization, are its specific characteristics? By producing an insurmountable disproportion between this problem, produced by history, and empirical historiography, this question leads necessarily to a philosophy of history.

Like most revolutions, the Protestant Revolution of the sixteenth century changed the existing socio-cultural realities far less than appears on the surface. To the Reformers themselves and most of their contemporaries the new ideas sounded startlingly novel, and their realization promised to alter the existing social and political structures to their very foundations. In fact, however, except for the overt changes in certain dogmatic and ritualistic postulates, specifically advocated by the new champions of Reform, life proceeded largely along accustomed lines.

The idea of sign, σημα (sema), has been popular in philosophy and the history of the sciences. Hippocrates and the Stoics, Plato and Aristotle, Saint Augustine and Descartes, Leibniz and Locke, Hegel and Humboldt figure among those who have dealt penetratingly with it. It has engendered a wide variety of sciences and disciplines: semiology, semiotics, semasiology, semantics, sematology which changed their name and content with the influence of time and sometimes of fashion, becoming forgotten to reappear with the impetus of a great thinker. The history of the sciences of the sign deserves systematic study. We shall content ourselves to point out that, of the terms quoted above, semiotics and semiology (or semeiology) have had a longer and richer career than the others. Since Greek antiquity they were applied to two apparently distant fields: military art (the science of manoeuvring troops with the help of signals) and medicine, in which they showed a greater perseverance. In many countries, throughout the 19th century and even today, medical study of the symptoms of illnesses is called semiology.

The idea of this study stems from two considerations: on one hand Western civilization has brought the audio-visual recording and broadcasting media to such a level of technical perfection that it has become possible to collect and broadcast documents regarding primitive peoples even in the most difficult conditions; on the other hand ever-widening strata of the “civilized” world are interested in the products, attitudes and spiritual world of primitive peoples which these technical media are now able to make known to them.

The rapid rhythm of material and psychic evolution that the non-industrialized (or insufficiently industrialized) societies of the African continent follow in this day and age inevitably outdates the writings of ethnologists at a similar tempo.

Nevertheless, the correctives that can be brought to bear on a vertical section often appear less considerable than the spectacular surface changes would have us presume. This is due, quite simply, to the remarkable resistance of the deep layers of the soul which conceal the obscure dynamic forces that model mentality or, if one prefers the expression, the ethnic personality.