The discussion of the four theses in Part One was intended in each case to make an ontological problem accessible to us. This was to be done in such a way that the four groups of problems thus arising would show themselves to be intrinsically a unit, the problems constituting the whole of the basic problems of ontology. The following emerged as the four basic ontological problems; first, the problem of the ontological difference, the distinction between being and beings; secondly, the problem of the basic articulation of being, the essential content of a being and its mode of being; thirdly, The problem of the possible modifications of being and of the unity of the concept of being in its ambiguity; fourthly, the problem of the truth-character of being.
We shall assign the four chapters of this second part each to one of these our basic problems.