(1) Ontological problem: what is reality?

(2) Metaphysical problem: has 2 forms, according to what may be considered reality. If we consider the world we see to be reality, then the met[aphysical] probl[em] is: (...)

If not, the met[aphysical] probl[em] becomes: what is the relation between that reality and the world? What is the world, if it be not reality?

From the solution of this problem, there follows the solutions of several other problems which depend upon it, for instance, the sociological problem, etc.

(3) The moral problem, or the problem of values (Nietzsche) .

The problem of relations of body and of soul I consider to be but a particular form of the great problem of matter and of force. This problem is the metaphysical problem. All the problems of science: problems of sociology, of anthropology, of geology and so on, in fine, the problems of cosmology are all parts of the metaphysical problem:

The metaphysical problem:

(1) Has the world a beginning in time and a limit in space?

(2) Is the actual world’s existence necessary or contingent?