Anaxagoras, the thoroughgoing infinitist

In the analysis of Anaxagoras’ physics in view of the relation between his teachings on multitude and heterogeneity, two central questions emerge: 1) How can the structure of the universe considered purely mereo-topologically help us explain that at the first cosmic stage no qualitative difference is manifest in spite of the fact that the entire qualitative heterogeneity is supposedly already present there? 2) How can heterogeneity become manifest at the second stage, resulting from the noûs intervention, if according to fragment B 6 such a possibility requires the existence of “the smallest”, while according to the general principle stated in fragment B 3 there is not “the smallest” but always only “a smaller”? This paper showcases the perplexity of these two questions but deals only with the former. The answer follows from Anaxagoras’ being a thoroughgoing infinitist in the way in which no Greek physicist was: the principle of space isotropy operative in geometry is extended to physics as well. So any two parts of the original mixture are similar to each other not only in view of the smaller-larger relation but also because each contains everything that the other one contains. This in effect means that at the stage of maximal possible heterogeneity each part of any part contains infinitely many heterogeneous parts of any kind whatsoever. So, neither can there be homogeneous parts in view of any qualitative property, nor can there be predominance in quantity of parts of any kind that would make some property manifest.

Anaxagoras (500–428 BC)

Anaxagoras of Clazomenae was a major Greek philosopher of the Presocratic period, who worked in the Ionian tradition of inquiry into nature. While his cosmology largely recasts the sixth-century system of Anaximenes, the focus of the surviving fragments is on ontological questions. The often quoted opening of his book – ‘all things were together’ – echoes the Eleatic Parmenides’ characterization of true being, but signals recognition of time, change and plurality. Even so, Anaxagoras is deeply committed to the Eleatic notions that, strictly speaking, there can be no coming into being or going out of existence, nor any separation of one part of reality from any other. His main object is to show how the variety of the world about us is somehow already contained in the primordial mixture, and is explicable only on the assumption that latent within each substance are portions of every other. Whether or not he owed his conception of unlimited smallness to Zeno of Elea, he held that there could be no such thing as a magnitude of least size; and he claimed that there was accordingly no difference in complexity between the large and the small. Mind, however, is a distinct principle; unlimited, autonomous, free from the admixture of any other substance. Hence Anaxagoras’ decision to make it the first cause of the ordered universe we now inhabit. Mind initiates and controls a vortex, which from small beginnings sucks in an ever-increasing expanse of the surrounding envelope. The vortex brings about an incomplete separation of the ingredients of the original mixture: hot from cold, dry from wet, bright from dark, and so on, with a flat earth compacted at the centre and surrounded by misty air and clearer ether above and below. Contemporaries were scandalized by Anaxagoras’ claim that sun, moon and stars were nothing but incandescent stones caught up in the revolving ether. Later fifth-century physicists – notably Archelaus and Diogenes of Apollonia – developed revised versions of Anaxagoras’ system, but abandoned his dualism. His conception of mind excited but disappointed Socrates, and exercised a profound influence on Plato’s cosmology and Aristotle’s psychology. Aristotle was also fascinated by the complexities of the remarkable theory of ‘everything in everything’. Anaxagoras’ philosophy was never subsequently revived, but he was remembered as the mentor of the statesman Pericles and the poet Euripides. His reputation as a rationalist critic of religion persisted throughout antiquity.

Improvement of the Efficiency of Perennial Seed Mixtures Separation on a Drum Vibro Electric Separator

Separation of seed mixtures plays a very important role in obtaining high‑quality seeds, which is characterized by the absence of hard‑to‑separate admixtures of weeds. The aim of the work was to improve the quality of seed mixtures of perennial grasses due to the use of the drum separator in the process of their additional cleaning. The conducted studies determined the basic geometric dimensions of the components of seed mixtures of perennial grasses and their coefficients of friction on various materials. The difference in their values was insignificant, as a result of which it was found that separating by these indicators is inappropriate. We can intensify the separation of the studied mixtures by using a drum vibro electric separator, where the separation takes place in a combination of frictional and electrical properties of the components. The main adjustable parameters of vibro electric separation established by previous studies were: the drum speed f = 8 rpn; the electric field of corona discharge E = 3.0 kV/cm; the oscillation frequency of the drum f1 = 50 Hz; drum amplitude A = 1,6 mm. With such parameters of separation we achieved the purity of the seed of the clover and the timothy grass in the range of 97…98 %, which, respectively, for 22.5 % and 17.5 % exceeds the purity of the original mixture.

Modification of the mechanical properties of rubbers by introducing recycled rubber into the original mixture

In our experimental work the opportunities of improving of mechanical properties of rubbers and their composites have been investigated. On the one hand the reuse of milling product of recycled rubbers (recycled crumb rubbers) has been studied and the effects of the filler and compatibilizers applicable in rubber composites on the mechanical properties either. The rubber composites were exposed to different mechanical stresses (tensile, fatigue tensile) and Shore A hardness and density of the specimens have also been determined. Morphology of the composites and the interaction between the fillers and the rubber has been studied on SEM graphs. Recycled crumb rubber was added in different concentrations to the basic mixture of rubber. Significant improvement of mechanical properties could be achieved by mixing 22m/m% used crumb rubber to the basic mixture. Tensile strength at break of composites containing recycled crumb rubber increased with nearly 20% compared to the original basic mixture containing no crumb rubber. Density decreased with 2-3% and Shore A hardness with 6% comparing the aforementioned composites. Different types of compatibilizing additives have also been applied in the system containing crumb rubber which showed different effectiveness in case of the properties, e.g. tensile strength at break. Adding compatibilizing additives to the basic mixture of rubber did not make the density changed while Shore A hardness changed similarly to the trend observed in case of tensile strength at break.

Perception of Mixture of Musical Instruments with Spectral Overlap Removed

The issue of auditory segregation of simultaneous sound sources has been addressed in speech research but was given less attention in musical acoustics. In perception of concurrent speech, or speech with noise, the operation of time-frequency masking was often used as a research tool. In this work, an ex- tension of time-frequency masking, leading to the removal of spectro-temporal overlap between sound sources, was applied to musical instruments playing together. The perception of the original mixture was compared with the perception of the same mixture with all spectral overlap electronically removed. Ex- periments differed in the method of listening (headphones or a loudspeaker), sets of instruments mixed, and populations of participants. The main findings were: (i) in one of the experimental conditions the removal of spectro-temporal overlap was imperceptible, (ii) perception of the effect increased when removal of spectro-temporal overlap was performed in larger time-frequency regions rather than in small ones, (iii) perception of the effect decreased in loudspeaker listening. The results support both the multiple looks hypothesis and the “glimpsing” hypothesis known from speech perception.

Research on New Green Camouflage Pigments

A pigment of Al2O3-CoO system has been prepared as a new green pigment for camouflage materials. The effect of the CoO content in the original mixture on the spectral reflectance of the pigment has been evaluated. The temperature condition of the pigment synthesis has been found. The pigment of Al2O3-CoO system has been modified as green camouflage pigment by ferric oxide, and the camouflage effect has also been estimated. The result shows that the pigment based on Al2O3-CoO system, as a substitute of Cr2O3, is a successful camouflage pigment.

Improvements in the selection of real components forming a substitute mixture for petroleum fractions

Complex mixtures, particularly petroleum fractions, usually need to be suitably modeled before providing the simulation and other types of chemical engineering calculations. The most convenient way is to describe the original mixture by a substitute mixture. The formerly published approach based on the employment of substitute mixtures of real components can be improved in order to get a closer match between the behavior of the original and substitute mixtures. In the first phase of the algorithm, a new concept of a band around the characterization curves brings wider possibilities for the selection of real components into the substitute mixture. The second phase, which is used to determine the composition of the substitute mixture, can be also improved by considering the global or bulk properties of the original mixture if available. Typically, some of the properties e.g. liquid density, molecular mass and PNA (Paraffinic/Naphthenic/Aromatic carbon) analysis can be measured and used to improve the adjustment of the composition. The improved algorithm is illustrated by an example.

Fighting Boys, Strong Men and Gorillas: Notes on the Imagination of Masculinities in Kinshasa

ABSTRACTThe article provides insight into the current violent practices of urban youngsters in Kinshasa. At nightfall youth gangs transform the streets of Kinshasa's townships into arenas of the fight. Frequent regular clashes between these gangs create young violent leaders, who not only sow terror but also provide security for the inhabitants (young and old) of their territories. Although many of these boys and young men are trained in foreign fighting styles such as judo, jujitsu and karate, in the public clashes between the fighting groups, these boys and young men performmukumbusu. This fighting style, inspired and based on the gorilla, was invented during the last decade of colonialism, and is an original mixture of a traditional Mongo wrestling practice,libanda, and Asian and Western fighting practices. In the article, I scrutinize the practices of these young fighters through the diverse images of masculinity (kimobali) upon which they draw, such as the fighter and the soldier; and the models of masculinity that they contest, thesapeurand thestaffeur.

Rondeau and virelai: the music of Andalus and the Cantigas de Santa Maria

Between the eighth and the thirteenth centuries the southern part of the Iberian Peninsula was dominated by its Arab and Berber conquerors and their direct political heirs. In this large and rich territory, called Andalus, an original mixture of Eastern and Western cultural elements gradually emerged. The southward expansion of the northern Christian kingdoms, beginning in the eleventh century, eventually displaced, circumscribed and debilitated Andalusian culture, which finally found in northwestern Africa its only stable refuge. Although the literary and artistic achievements of Andalus have long attracted attention, the place of music in medieval Andalusian culture has not lately been subject to close scrutiny. The present study, based largely on the analysis of Andalusian survivals in contemporary North African musical traditions, will attempt to identify what could have been the most typical musical forms of Andalusian song and evaluate their possible influence on the thirteenth-century Cantigas de Santa Maria and French secular song.