a discontinuous and qualitative change in the dynamical (time-dependent) pattern of the observable (Guckenheimer and Holmes, 1993; Wiggens, 1990; see Strogatz, 1994, for a particularly intuitive description). Qualitative here means how the dynamics of the trajectory appear as a geometric-topological (relati

Fadiga, L (2001). Modulation of spinal excitability during observation of hand actions in humans, Huropean Journal of Neuroscience, 13, 190 -194. * Strogatz, S. (2003). Rhythms of nature, rhythms of ourselves. London: Allan Lane. ? Tognoli, E., Lagarde, J., DeGuzman, C. D., Kelso, J. A. S. (2007). The ph

uthor, who brings the story of calculus to life in a single narrative that spans continents, centuries, and disciplines to a dramatic climax. Writes Strogatz, "The quest to tame infinity, and to harness it toward our ends, is a narrative that runs through the whole 2,500-year story of calculus. Yet this s