Formalizing the transformations of a cognitive universe

International audienceIn an effort to continue the pioneering work of Harary in USA and Flament in France, we have undertaken to develop, on an experimental basis, a formalized theory of systems of beliefs and their modifications. This theory uses the psycho-social concepts of theories of cognitive consistency and of the tools of discrete mathematics, such as rewriting and intervals within graphs. The axioms and rewriting rules are elaborated from experimental data, and we demonstrate that the system we have built has the property of termination. This result is in accordance with experimental observations that show that every subject having an inconsistent system of beliefs (i.e., one containing contradictions) makes this system evolve towards consistency to reach a simple, consistent reference framework

Do All Lives Have the Same Value? Support for International Military Interventions as a Function of Political System and Public Opinion of the Target States

This research examined the support for international military interventions as a function of the political system and the public opinion of the target country. In two experiments, we informed participants about a possible military intervention by the international community towards a sovereign country whose government planned to use military force against a secessionist region. They were then asked whether they would support this intervention whilst being reminded that it would cause civilian deaths. The democratic or nondemocratic political system of the target country was experimentally manipulated, and the population support for its belligerent government policy was either assessed (Experiment 1) or manipulated (Experiment 2). Results showed greater support for the intervention when the target country was nondemocratic, as compared to the democratic and the control conditions, but only when its population supported the belligerent government policy. Support for the external intervention was low when the target country was democratic, irrespective of national public opinion. These findings provide support for the democracy-as-value hypothesis applied to international military interventions, and suggest that civilian deaths (collateral damage) are more acceptable when nondemocratic populations support their government's belligerent policy

Evolution of field-induced metastable phases in the Shastry-Sutherland lattice magnet TmB4

The appearance of a plateau in the magnetization of a quantum spin system subject to continuously varying magnetic field invites the identification of a topological quantization. Indeed, the magnetization plateaus at 1/8 and 1/2 of saturation in TmB4 have been suggested to be intrinsic, resulting from such a topological quantization, or, alternatively, to be metastable phases. By means of neutron- and x-ray-scattering experiments and magnetization measurements, we show that the 1/8 plateau is metastable, arising because the spin dynamics are frozen below T ≈ 4.5 K. Our experiments show that in this part of the phase diagram of TmB4, many long-ranged orders with different propagation vectors may appear and coexist, particularly as the applied field drives the system from one plateau to another. The magnetic structures accommodating a magnetization of ≈1/8 seem to be particularly favorable, but still only appear if the system has sufficient dynamics to reorganize into a superstructure as it is driven toward the expected plateau. This work demonstrates that TmB4 represents a model material for the study of slow dynamics, in and out of equilibrium

Cognitive and affective judgements of syncopated musical themes

This study investigated cognitive and emotional effects of syncopation, a feature of musical rhythm that produces expectancy violations in the listener by emphasising weak temporal locations and de-emphasising strong locations in metric structure. Stimuli consisting of pairs of unsyncopated and syncopated musical phrases were rated by 35 musicians for perceived complexity, enjoyment, happiness, arousal, and tension. Overall, syncopated patterns were more enjoyed, and rated as happier, than unsyncopated patterns, while differences in perceived tension were unreliable. Complexity and arousal ratings were asymmetric by serial order, increasing when patterns moved from unsyncopated to syncopated, but not significantly changing when order was reversed. These results suggest that syncopation influences emotional valence (positively), and that while syncopated rhythms are objectively more complex than unsyncopated rhythms, this difference is more salient when complexity increases than when it decreases. It is proposed that composers and improvisers may exploit this asymmetry in perceived complexity by favoring formal structures that progress from rhythmically simple to complex, as can be observed in the initial sections of musical forms such as theme and variations