The nervous system, and particularly the cerebral cortex, is examined in certain of its activities, it being treated as a purely physical dynamic system. It is shown mathematically that if, as seems likely, the cerebral cortex can undergo manifold changes of neuronic organization, then it follows that these changes must automatically lead to the development of more and more states of equilibrium, the process being unavoidable and largely irreversible. The theorem may be established on basic physical principles without appeal to special physiological details. The possible significance of this observation is indicated.

In the absence of sound units of measurement, the data obtained by use of a psychometric instrument may sometimes be so irregular that they cannot be accepted as a good representation of the true function of the trait measured. Frequently, ordered categorical or ranked data and other irregular distributions are obtained to represent traits that are obviously continuous and probably unskewed functions. In such cases, the data may be improved in the direction of a better approximation of the true function by converting them to normal distribution form. A table of mean deviates of various portions of the unit normal curve is presented to facilitate this conversion.

Two formulas are presented for judging the significance of the difference between correlated proportions. The chi square equivalent of one of the developed formulas is pointed out.