Observational learning can enhance the acquisition and performance quality of complex motor skills. While an extensive body of research has focused on the benefits of synchronous (i.e., concurrent physical practice) and non-synchronous (i.e., delayed physical practice) observational learning strategies, the question remains as to whether these approaches differentially influence performance outcomes. Accordingly, we investigate the differential outcomes of synchronous and non-synchronous observational training contexts using a novel dance sequence. Using multidimensional cross-recurrence quantification analysis, movement time-series were recorded for novice dancers (...) who either synchronised with (n = 22) or observed and then imitated (n = 20) an expert dancer. Participants performed a 16-count choreographed dance sequence for 20 trials assisted by the expert, followed by one final, unassisted performance trial. Although end-state performance did not significantly differ between synchronous and non-synchronous learners, a significant decline in performance quality from imitation to independent replication was shown for synchronous learners. A non-significant positive trend in performance accuracy was shown for non-synchronous learners. For all participants, better imitative performance across training trials led to better end-state performance, but only for the accuracy (and not timing) of movement reproduction. Collectively, the results suggest that synchronous learners came to rely on a realtime mapping process between visual input from the expert and their own visual and proprioceptive intrinsic feedback, to the detriment of learning. Thus, the act of synchronising alone does not ensure an appropriate training context for advanced sequence learning. (shrink)

In its reaction on the terroristic attacks of September 9th, 2001, the US-government threatened Afghanistan's Taleban with war in order to force them to extradite terrorist leader Bin Laden; the Taleban said that they would not surrender to this kind of blackmail – and so, they were removed from Kabul by means of military force. The rivalling versions of this story depend crucially on notions such as "terrorism" and "blackmail". Obviously you'll gain public support for your preferrend version of the (...) story if you are able to determine how those notions are to be used. So we had better reflect about their very meaning and about the moral implications of their proper usage. To gain a deeper understanding of our notions of "blackmail" and "terrorism" I shall propose an extreme thought experiment: Cassandra's plan. Cassandra foresees that sooner or later one of the nuclear powers might take the liberty to use atomic bombs. From fright she founds an NGO for blackmailing the statesmen who are in charge of nuclear weapons; she announces in public that all ministers and leaders of any government shall be hunted down, and executed, whose soldiers drop but one atomic bomb. (Cassandra's NGO keeps killer teams in constant training so as to increase the effect of the threat; this is being financiated from private donations). In my paper I shall raise two questions (without claiming to provide definite answers). First, would we have to say that Cassandra's NGO was a terrorist organisation? Second, would it be morally wrong if Cassandra blackmailed statesmen in the way indicated? (shrink)

In the wake of the global financial crisis of 2008, the greatest economic disaster since the Great Depression, the cover story of the July 18th 2009 issue of The Economist, entitled “What went wrong with economics,” opened with an unequivocally incriminating statement: “Of all the economic bubbles that have been pricked, few have burst more spectacularly than the reputation of economics itself.” In the months surrounding this indictment, many influential economists, including several Nobel laureates, were drawn to the same embarrassing (...) conclusion. Despite the existence of a handful of Cassandras, economists, as a group, had failed to foresee the crash. This short essay reviews the criticisms addressed to modern economic theory in the immediate aftermath of the crash. Overall, the main issues raised by critics were that (a) economists versed in the dominant models in macroeconomics and finance have been blinded to the possibility that we live in an uncertain and complex world; and (b) that the content of current economics education has sidelined many of the relevant insights to be found in the history of the discipline. This has led the critics to call for changes in the institutional structure of discipline, with a particular emphasis on the promotion of interdisciplinarity, and theoretical and methodological pluralism. (shrink)