The slave route from Africa to the Americas is as old as the contact between Europe and the New World itself, and the slave route across the Sahara is older still. Hence to describe the lives of ordinary people in western Africa during the era of slavery would require an examination of the whole of African history over the past five hundred years and more. And in Africa, as in Europe and the Americas, there was tremendous change over this period and extensive variation at any point in time. Life in 1807, when Britain and the United States outlawed the slave trade, was considerably different than in 1492, when Columbus first sailed to the Caribbean. Hence to give an impression of how people in Africa lived during the era of transatlantic slavery is also to understand how the lives of people changed over the course of the slave trade. In 1492, a coup d’état brought a Muslim ruler, Askia Muhammad, to the throne of the great empire of Songhay, and for the next hundred years, Songhay ruled much of West Africa. As empires have always done, Songhay's influence extended to areas beyond its military control. At this time, the slavery of Africans in the Americas was in its infancy. Yet, in 1593, a military invasion from Morocco across the Sahara destroyed Songhay, and much of the internal cohesion of western Africa came to an end, precisely when transatlantic slavery emerged as the principal means of exploiting the agricultural and mineral wealth of the Americas. The lives of ordinary people changed because of this monumental collapse of Songhay. Similarly, the changes imposed by European abolition of the slave trade after 1807, although confusing and often delayed in their impact, were also monumental. Hence the first task in considering how people lived during the slavery era is to identify the differences over time that affected both people who were forced, through slavery, to cross the Atlantic and those who remained behind in Africa. Africa in 1492 or 1593 was not the same as in 1807, any more than Europe and America were.

In order to establish itself as a discipline, it was not enough for sociology to disassociate itself from philosophy and psychology. The lines appearing in the above epigraph, published exactly one hundred years ago, remind us of what is often not considered in the difficulty of establishing social sciences in the world as a whole: first – and as a question of priority – disciplines had to fight the widely prevailing influence jointly held by evolutionism, “social Darwinism,” and “biological sociology” at the end of the nineteenth century. Durkheim's methodological warning thus contains something that elicits a “feeling of déjà vu” in us, with respect to some of the theoretical debates that the “scholarly community” puts forward today for the general public. Is this simply a superficial and somewhat coincidental similarity, or is it, rather, the rebirth of an idea?

Ten years ago, an issue of the journal L'Homme et la Société was entitled “La Mode des identités.” Most of the articles were about cultural identity, but the basic thrust of the work was “a critique of the ‘fashion’ of identity calling into question the validity of a notion as striking as it is uncertain.” Recently, a special issue of the journal Sciences Humaines, entitled “Identité et identités,” dealt with personal, familial, social, professional identities and only spoke of cultural identity marginally and in a roundabout way. Finally, in a manual of Sociologie politique published by the Presses Universitaires de France, the author takes to task the notion of ethnicity inherent to cultural identity and pushes the critique of the ethnic group to the point of negating its objective existence. Must we think then that the notion of cultural identity is henceforth obsolete, that it has lost all pertinence?

There is a hint of paradox in opening this collection of texts on the procedures for totalizing knowledge in Antiquity by calling to witness the Platonic dialogues. What might they contribute, besides a critique of Sophistic polymathy, Socrates’ nescience, his way of jumping in and interrupting long discourses, the disconcerting interlude of preliminary questions, and the aporetic collapses? A host of questions does not make a book, much less a library - unless the Socratic stratagem defines some entirely new conditions, or unless Plato's argument authorizes, beyond a program of study, a way of constituting knowledge with its hierarchized elements and the articulations called for by this program. A few remarks are in order here.

A citizen of Early Renaissance Florence that stepped out into the streets and entered the spaces of his civic world joined a concert of creative formal behaviors in which he was at once an actor and a spectator. His problem here was to interpret the complex web of overlapping, conflicting and simultaneous meanings he would have read in the actions and images by which the community directed him and represented itself, and find his own place and set his standing. On most occasions he would probably have elected for a state of suspension, a floating of multiple possibilities he was loath to precipitate in too stable a form: in ambiguity the citizen of Florence developed a richness of signification, and found a refuge.

Aristotle's endeavor, at least insofar as we can judge from the way it has been transmitted to us and from the titles of the lost works, is often presented as the first work of an encyclopedic nature, as it seems to embrace and order all of the elements of knowledge. Does Aristotle not advance a classification of sciences, in Metaphysics, E, 1, as well as a systematic outline of the “sciences of nature” in his Meteorologica, I, 1? And again, although logic is often presented as not belonging to the system of sciences since it is not counted as a science in Metaphysics, E, 1, is Aristotle not generally considered the inventor of this discipline? The impression is all the stronger in that Andronicus of Rhodes, in the first century b.c., edited Aristotle's works by roughly adopting the threefold division of philosophy into Logic-Physics-Ethics, a division that had become common during the Hellenistic period though more particularly proper to the Stoic system. Since then, all the editions of Aristotle, in every language, have been made to serve the order in which Aristotle's treatises were thus edited.

From its very beginnings, this century has been under the sign of genetics. Indeed, it was in 1900 that the laws established by Mendel in the mid-nirieteenth century were rediscovered. In that same year, Landsteiner identified the first human blood typing, the ABO system. At that time, agronomists, eugenicists, and physicians were the principal agents of the development of genetics. The chromosome theory of heredity was asserted beginning in 1911; it was followed in the 1940s by the understanding of the role of the gene in cellular metabolism, and in 1954 by the explanation of the structure of the DNA double helix. The pre-eminence of genetics was to increase through the second half of the century, particularly in the 1970s with the advent of genetic engineering.

When Captain Binger traveled the Niger bend between 1887 and 1889, he saw numerous villages that had been drained of their lifeblood or left in ruins by violent conflicts that had left their mark in the form of fortifications. Above all he was struck by the region's depopulation, which threatened to compromise the potential for colonial exploitation of the country. But these conditions did not prevail throughout the entire area. Prosperous towns were engaged in trade, war parties were living in ostentation, and rulers were collecting taxes from their subjects. The misery of the peasants’ lives contrasted with the opulent luxury of the courts and caravansaries. The black slave trade, and slavery itself, did not exert a uniform effect upon all of Africa.

The UNESCO research projects focusing on The Silk Routes and The Slave Routes were launched at just the right time to remind us that globalization is not a novel dimension of the history of humanity. Not only am I among those who analyze capitalism as a worldwide system from its very inception, but I have also found it pertinent to recall that prior to the sixteenth century, societies were not at all isolated from one another but rather competing within regional systems (and perhaps within one global system). To underestimate this fact is to condemn ourselves to a misunderstanding of the very dynamics of change within societies. At the same time, I maintain that in the history of the world, capitalism represents a qualitative rupture that had its beginnings around 1500. Accordingly I emphasize the distinction that must be made between the integrated structure of the worldwide capitalist system and the protocapitalist elements that are to be found in earlier societies; I also underline the specificity of the contrast between centers and peripheries, which is unique to global capitalism and which differs from previous forms of polarization.

One of the characteristics of this ending century might very well be the resurgence of ethnic, nationalist, and fundamentalist movements, a group of manifestations conveniently designated by S. Huntington in the expression “the clash of civilizations.” Although in the West we live, since the end of the nineteenth century, in the paradigm of class struggle - even despite the fact that World War I fighters had proven that they accepted to “die for their country” - the 1990s seem to toll this model's bell in favor of a hardening of identity demands.

What does “encyclopedic knowledge” mean to us today? I believe that, as in the eighteenth and nineteenth centuries, what we mean by this term is a knowledge that strives to embrace in detail the greatest possible number of sciences and bodies of knowledge. As Sainte-Beuve said in 1850 regarding Madame de Genlis:

The primary method by which science endeavors to order the world is the analytic approach, consistent with Cartesian principles of dividing the problem in as many sections as required for an optimal solution, and progressing from the simplest to the most complex reasoning. When the interactions among the various elements of the system being studied are minimal, such a procedure indeed makes it possible to formulate laws that describe chains of causality. However, when the variables are interdependent and linked by non-linear equations, the atomistic method cannot account for the phenomenon in its entirety. Spurred by this inadequacy, scientists sought to discover synthetic methods which, early in the twentieth century, led to the conceptualization of holistic theories in a number of disciplines. The most highly developed fields are the psychology of form, structural anthropology (1), and the various systems theories (2). More recently, the development of epigenetic concepts in biology has corresponded to the appearance of different theories of pattern in physics and mathematics (3, 4) and to the progressive emergence of the concept of self-organization (5, 6, 7). The objective is to explain the production of complex structures on the basis of interacting elements, none of which contains a guiding scheme that dictates these structures. In biology, the challenge is to locate the constraints that are expressed in a space of possibilities (8) in order to develop a theory of organization that is capable of predicting the finite number of forms that living creatures can assume (9). This school of thought can be described as structuralist, emergentist, self-organizational, or epigeneticist, depending on the theoretical version that is emphasized.

The Letter of Aristeas, a text written in Greek by a Jewish author of the Alexandrian diaspora, probably in the second century b.c., traces the circumstances under which a Greek translation of the sacred book of the Jews, the Pentateuch, was commissioned by King Ptolemy II Philadelphus. The letter situates this undertaking in the broader context of the foundation of the Library of Alexandria on the advice of Demetrius of Phalerum, who instigated the plan to gather together all the world's books, both those in the possession of the Greeks and those “of other peoples.”

The history of the African slave trade, despite its importance and role in world development, was not scientifically studied until 1930, and even since then few books and papers have been devoted to the subject. Beginning in the nineteenth century, however, this history has been the focus of sensational publications that underline and broadly interpret a smattering of highly emotional events. A conspiracy of silence cloaks the subject, as though shame still weighs upon the shoulders of Western society. In Africa, the same silence seems to favor consigning all memory of the collaborators to oblivion. In the last twenty years, the situation has begun to change. Several international conferences have brought together white and black historians. The Anneaux de la mémoire (Chains of Memory) exposition in Nantes enjoyed considerable success, and in 1994 UNESCO launched a decade-long cultural program called La Route de l'esclave (The Path of Slavery).

The cultures here in question are those of mathematics and of physics that I shall interpret with the goal of exploring different modes of creativity. As case studies I will consider two scientists who were exemplars of these cultures, the mathematician Henri Poincaré (1854-1912) and the physicist Albert Einstein (1879-1955). The modes of creativity that I will compare and contrast are their notions of aesthetics and intuition. In order to accomplish this we begin by studying their introspections.

The study of human origins is a kaleidoscopic field, a multitude of objects, reflections, and disciplines a swirl in an ever-changing tumult. The extreme diversity of the elements of information that are indispensable to this field of study (teeth, bones, apes, genes, ancient objects, present-day objects, biomechanical factors, cultural constructions …) appears all by itself to be enough to consign any attempt at synthesis to the realm of the Utopian. It hardly seems reasonable to expect the disparate sciences that fuel the field (paleoanthropology, archaeology, molecular biology, physics, psychology, and others) and the contradictory conceptions of scientific activity that they defend (human sciences, natural sciences, experimental sciences, exact sciences) to be joined with any regularity. As for formulating an overall problematics of the interdependent phenomena encountered in the field, one would have to be more than optimistic to entertain such dreams. And yet this is exactly the program that prehistory and paleoanthropology are laboring to construct tinder the label “the study of the origins of man,” an expression that includes both diachronic processes (human evolution) and activities or behaviors from particular moments, elements that are exceedingly difficult to compare given the separation of their geographic and temporal contexts.