MARXISM AND QUANTUM MECHANICS 79 a new phenomenon, a new process with its intrinsic contradiction. It is the existence of different contradictions at different levels of matter that I should like to stress. We use categories of dialectical opposites to express the contradictions at any given level. But having described the motion at this level in terms of a certain pair of opposites, it would be undialec-tical to expect the same pair of opposites to provide the conceptional tools to investigate the behaviour of matter at deeper levels. Let us take an example. We explain electric phenomena in terms of positive and negative charges. Consider the Fermi process where the neutron (an uncharged particle) decays into a proton (+), an electron (-) and an antineutrino (uncharged). In the reverse reaction a proton^ electron and antineutrino convert into a neutron. Now, what has happened to the positive charge of the proton and the negative charge of the electron when they form the neutron? Have they just vanished completely from nature? It is certainly not enough to give the algebraic explanation that the positive has cancelled the negative. The charges persist within the neutron existing in an implicit, latent form, passing to a deeper levc^ of matter with its intrinsic contradictions. To insist that the contradictory processes within the neutron can be explained in the same categories of positive-negative is to fail to recognize the qualitative infinity of matter in depth. Engels warned us against this rigidity engendered by our categories of thought when he wrote: It is however precisely the polar antagonisms put forward as irrecon cilable and insoluble, the forcibly fixed lines of demarcation and class distinctions, which have given modern theoretical natural science its restricted metaphysical character. The recognition that these antagonisms and distinctions, though to be found in nature, are only of relative validity, and on the other hand their imagined rigidity and absolute validity have been introduced into nature only by our reflective minds—this recognition is the kernel of the dialectical conception of nature.12 The expectation that all further advances in quantum theory will proceed with the conceptional tools of wave-particles.continuous-disconti-nuous and necessity-chance is like imagining human evolution to have restricted itself to the use of such primitive tools as the pointed flint and the stone axe. K K THRCKRDATH ' Social Scientist 35, June 1975. 2 Social Scientist 25, August 1974, 8 Maurice Cornforth, Dialectical Materialism, National Book Agenry, Calutta 1971, p 2o. 4 VI Lenin, Left Wing Communism^ an Infantile" Disorder. ^ David Bohm, Causality and Chance in Modern Physics, Routledge and Kcgan Pau1> London 1957. 6 Yu V Sachkov, ^An Appraisal of Statistical Regularities in Elementary-Particle