  Very recently we present a theory to discuss the nature of light and show
that the quantization of light energy in vacuum can be derived directly from
classical electromagnetic theory. In the theory a key concept of stability of
statistical distribution and a variational procedure searching for those of
relatively stable statistical distributions were introduced. This is a
classical interpretation to the concept and method concerned. It would be
helpful for avoiding some of possible obsession from the variational procedure
and its final quantum result.
