The dynamics of Machiavellian intelligence

The "Machiavellian intelligence" hypothesis (or the "social brain" hypothesis) posits that large brains and distinctive cognitive abilities of humans have evolved via intense social competition in which social competitors developed increasingly sophisticated "Machiavellian" strategies as a means to achieve higher social and reproductive success. Here we build a mathematical model aiming to explore this hypothesis. In the model, genes control brains which invent and learn strategies (memes) which are used by males to gain advantage in competition for mates. We show that the dynamics of intelligence has three distinct phases. During the dormant phase only newly invented memes are present in the population. During the cognitive explosion phase the population's meme count and the learning ability, cerebral capacity (controlling the number of different memes that the brain can learn and use), and Machiavellian fitness of individuals increase in a runaway fashion. During the saturation phase natural selection resulting from the costs of having large brains checks further increases in cognitive abilities. Overall, our results suggest that the mechanisms underlying the "Machiavellian intelligence" hypothesis can indeed result in the evolution of significant cognitive abilities on the time scale of 10 to 20 thousand generations. We show that cerebral capacity evolves faster and to a larger degree than learning ability. Our model suggests that there may be a tendency toward a reduction in cognitive abilities (driven by the costs of having a large brain) as the reproductive advantage of having a large brain decreases and the exposure to memes increases in modern societies.Comment: A revised version has been published by PNA

Research on the Efficacy of Creative Risk Management Approach based on Reverse Thinking

AbstractBased on Sabotage Analysis as one of TRIZ techniques, we developed Creative Risk Management Approach based on Reverse Thinking (CRMART). CRMART is very effective not only as a method to prevent human errors at site of work in manufacturing and construction industries but also as a risk management method based on future-oriented thinking against New-Type Risks (NTR) in IT field with drastic advances in technical innovations. Introducing CRMART in a variety of real projects, we have got a reputation from practitioners who experienced CRMART through risk management activities.Judging from the above, it is clear that CRMART really plays the field and is flexible method. And now, reverse thinking in CRMART comes from “Other Way Round” called No.13 principle in 40 Inventive principles. However, the most important feature of CRMART is that the risk factors we grasp get converted to functions we should practice by utilizing Functional Analysis (FA) in Value Engineering (VE). Because it's possible to move the risk factors from non-participant observer to central player in a risk management activity logically by transforming risk factors from usual risk items into functions. Putting risk factors to central players means that capacity for imagination regarding the process coming up risks could be improved. That is to say, it is clear that capacity to respond to unanticipated risks has risen.Therefore, in this paper, we want to introduce a case study about proposed measures against divulging of information at a company as a typical unanticipated risk in information society, contrasting a case study we applied with proposed procedure of CRMART. Lastly, we would like to organize the advantages of this method as specific observer's eye as possible

Temperature Dependent Polarity Reversal in Au/Nb:SrTiO3 Schottky Junctions

We have observed temperature-dependent reversal of the rectifying polarity in Au/Nb:SrTiO3 Schottky junctions. By simulating current-voltage characteristics we have found that the permittivity of SrTiO3 near the interface exhibits temperature dependence opposite to that observed in the bulk, significantly reducing the barrier width. At low temperature, tunneling current dominates the junction transport due both to such barrier narrowing and to suppressed thermal excitations. The present results demonstrate that novel junction properties can be induced by the interface permittivity

A new determination method of interatomic potential for sodium silicate glass simulations

An interatomic potential for the classical molecular dynamics (MD) simulation of sodium silicate glasses was proposed. The ionic charges for this interatomic potential were determined by Mulliken population analysis via the density functional theory (DFT) calculation of alkali silicate crystals. The Si-O interatomic potential energy curve was determined by molecular orbital (MO) calculation of SiO2 +. The results of classical MD simulations using the new interatomic potential were consistent with the experimental trends in interatomic distance, thermal expansion coefficient, molar volume, Si-O-Si bond angle distribution, and Qn ratio with respect to the sodium composition of the silicate glass. The proposed interatomic potential improves the reproducibility of the ring size distribution in silicate glasses compared to conventional potentials