Editing Principia Mathematica (section)

== Scope of foundations laid ==

The ''Principia'' covered only [[set theory]], [[cardinal numbers]], [[ordinal numbers]], and [[real numbers]]. Deeper theorems from [[real analysis]] were not included, but by the end of the third volume it was clear to experts that a large amount of known mathematics could ''in principle'' be developed in the adopted formalism. It was also clear how lengthy such a development would be.

A fourth volume on the foundations of [[geometry]] had been planned, but the authors admitted to intellectual exhaustion upon completion of the third.