  We propose an alternative approach to construct an artificial learning
system, which naturally learns in an unsupervised manner. Its mathematical
prototype is a dynamical system, which automatically shapes its vector field in
response to the input signal. The vector field converges to a gradient of a
multi-dimensional probability density distribution of the input process, taken
with negative sign. The most probable patterns are represented by the stable
fixed points, whose basins of attraction are formed automatically. The
performance of this system is illustrated with musical signals.
