Of course there may well be particular reasons why Spencer rather than others is dead, as there were also particular reasons why he rather than others made such a stir.

Spencer's god was Evolution, sometimes also called Progress.

If there are four equations and only three variables, and no one of the equations is derivable from the others by algebraic manipulation then there is another variable missing.

Theory not only formulates what we know but also tells us what we want to know, that is, the questions to which an answer is needed.

A theoretical system does not merely state facts which have been observed and that logically deducible relations to other facts which have also been observed.

In so far as such a theory is empirically correct it will also tell us what empirical facts it should be possible to observe in a given set of circumstances.