Actualité d’une philosophie des machines

On the mode of existence of technological objects (1958) remains a strange work on the philosophical horizon. Yet, all along his career, Gilbert Simondon has expressed himself on technique. The originality of his works is the analysis of machines as organised matter. This orientation sends us back to the divergence between French and German research on technique in the 20 ^th century. Simondon joins mecanology to a psycho-sociology of techniques. In view of an operational reactualisation these two approaches are put to the test of the Large Hadron Collider (LHC) and to the psychosocial “halo” of the nanotechnologies.     

The Still Bay points of Blombos Cave (South Africa)

We present the results of a technological and morphometric analysis of all the Still Bay points (n = 371) recovered from the 1993 to 2004 excavations at Blombos Cave. We have been able to reconstruct the manufacturing sequence of the bifacial points from initial shaping, by direct internal percussion, to finished morphology, by direct marginal percussion. Identifications of impact fractures and manufacturing breaks are based on comparisons with experimental and archaeological bifacial points of verified function, i.e. Paleoindian points from bison kill sites, replicates of Solutrean points mounted as spear-heads or arrowheads and shot into adult cattle, and experimental replication on local raw materials. Our analysis shows that: (a) only a minority of the points are finished forms, and that a large number of pieces are production failures, a situation known at bifacial point production sites of later ages; (b) morphometric and impact scar analyses should take into account this process and distinguish finished points from preforms and unfinished points; (c) there were at least three different kinds of raw material sources and that there is a marked increase in the frequencies of silcrete with respect to the M2 and M3 phases at Blombos; (d) three kinds of evidence prove that some of the points were hafted axially and used as spear tips; (e) production of bifacial points was a primary activity at the site but the hypothesis of intergroup exchange of Still Bay points cannot be sustained on the basis of present evidence; and (f) the Still Bay phase appears to initiate a trend to relatively rapid changes in specialized hunting weaponry and that this innovation is congruent with other innovations such as bone tools, shell beads and engraved ochre of the M1 and M2 phases at Blombos.     

Diffraction around a Semi-Parabolic Canyon in an Elastic Half-Space by Out-of-Plane SH-Waves,II: Rocking and Resultant Rotations

This paper is the second of the two papers, discussing the rocking and resultant component of rotations, with the torsional components of motions presented earlier in the first paper for the case of out-of-plane SH waves excitation on a semi-parabolic canyon. The rotational motions are gaining importance in recent years in the field of strong-motion seismology and earthquake engineering. Many previous papers on out-of-plane SH waves excitation presented the associated torsion rotational motions, when in fact there is also a rocking rotational component of motions. Both the rocking and torsion rotational motions, in as much as the translational motions, had shown to play an important role in structural responses, even though rotations are not incorporated into building design codes at present. Studying the rotational motions can thus help to a better understanding of the behavior of surface topographies that are in the vicinity of structures in the event of seismic excitation. This paper included, besides the additional rocking motions, also the resultant rotational motions combining torsion and rocking.     

A Neolithic innovation in eastern Arabia: haematite axes and adzes

Well before metallurgy, Neolithic societies in the Gulf were engaging in a very peculiar form of metal object production, particularly of axes and adzes made from haematite. In the heart of the Neolithic Middle East, this innovation was specific to Arabian shores between the Musandam and Qatar peninsulas. Quite infrequent among Neolithic lithic assemblages from Arabia, axes and adzes were mostly collected on the surface of domestic settlements. One is often dealing with objects to which the most focus has been given, apart from arrowheads and projectile points. Several sites or outcrops are present on the Emirati coastline and Gulf islands. Inland mountain ranges also include some of these. From Ra’s al-Khaimah to Qatar, only 500 km separate the most distant Neolithic domestic settlements which possess haematite axes or hoes, a distance that is quite small when one considers the circulation of polished stone blades in other societies of the same period. Within the Middle East, south-eastern Arabia during the Neolithic engaged in a very original means of production of metal objects, as the latter did not focus on copper, a very malleable and much more available material, but on haematite, which was much harder.     

The Chemists' Style of Thinking

Der Denkstil der Chemiker. Der Aufsatz diskutiert die Tragfähigkeit des Begriffes “Denkstil”, wie er von Alistair Crombie eingeführt und Ian Hacking aufgegriffen wurde, für das Verständnis dessen, wie das Fach Chemie historisch seine Identität ausgeprägt hat. Obwohl weder Crombie noch Hacking den Begriff “Denkstil” in Bezug auf einzelne Disziplinen verwendet haben, erscheint im Fall der Chemie seine Anwendung besonders vielversprechend, weil er hier hilft, ein zentrales Problem zu thematisieren – nämlich die Frage, wie es Chemikern trotz wechselnder Gegenstandsbereiche und theoretischer Umbrüche gelang, eine eigenständige und stabile Identität auszubilden. Nach einer Einführung in den Begriff “Denkstil”, argumentiert der Aufsatz, dass die Beständigkeit der Chemie als eines Faches wesentlich in ihren Laborpraktiken gründet, die ihrerseits wiederum die spezifische Art der Fragen bestimmten, die Chemiker in ihren Forschungen stellten bzw. die Form der Antworten, nach denen sie suchten. Folgende Merkmale kennzeichnen diesen “chemischen Denkstil” (1) eine spezifische, im Herstellen begründete Form des Wissens, (2) die Befassung mit einzelnen Stoffen und Materialien statt mit Materie im Allgemeinen und (3) eine Beobachtung von Natur besonders im Hinblick auf Transformationsprozesse. The Chemists' Style of Thinking. This paper discusses the relevance of the notion of “styles of scientific thinking” introduced by Alistair Crombie and revisited by Ian Hacking, for understanding how chemistry shaped its identity. Although neither Crombie nor Hacking applied this notion to individual disciplines, it seems appropriate to use it in the case of chemistry because it helps to address a puzzling issue: how did chemists manage to shape an identity of their own, despite shifting territories and theoretical transformations? Following a presentation of the notion of style, I will argue that the stable identity of chemistry is rooted in laboratory practices, which determined the specific questions that chemists put to nature as well as the answers to their questions. The “chemical style of thinking” is characterized by i) a specific way of knowing through making, ii) the concern with individual materials rather than matter in general and iii) a specific commitment to nature.