 Contrary to König, Richard did not rely upon the well-ordering of the continuum, and the proposed solution is interesting for the foundational debate to come. He pointed out that the definition of the number \(N\) refers to the totality of definable reals, to which \(N\) itself belong; but no object should be definable in terms of a collection containing it. So it appears that the definition is viciously circular, and that makes the definition illusory. This idea soon became the basis of Poincaré’s solution, and eventually also Russell’s (see below  3.1,  the issue of impredicatively defined collections).