ABSTRACT
Today' is at the front edge of time. It moves continuously forward with an ever lengthening past behind it. Any event that occurred at any date in history occurred when that date was 'today'. In a properly specified stationary state, there is no distinction between any one day and any other. On a properly specified growth path, such as a von Neumann ray, exhibiting a particular pace of expansion of employment and of a specified stock of means of production, there is no movement forward and upward or backward and downward. In expounding economic theory, the statement is often made that such and such will happen 'in the long run'. For Marshall, the long run is a period of future time after some event has occurred. An unforeseen rise in the demand for fish, at a certain date, causes its price to rise.
