 Principal 1: The principle of partial control (Altenberg, 1984)
When variation has only partial control over the transformations occurring on types under selection, then it may be possible for the part which it controls to evolve an increase in rates.
 Principal 2:
Partial Control and Induced Directed Variation (Altenberg, 2012)
Undirected variation of a transformation process, i.e. equal scaling of all transition probabilities by a rate m, may act effectively like directed variation toward fitter types due to dynamics induced by other transformation processes and selection, so that increases in m increase the population growth rate r.
