Again an entity cannot stand in external relations unless in its essence there stands an indeterminateness which is its patience for such external relations. The meaning of the term ‘possibility’ as applied to _A_ is simply that there stands in the essence of _A_ a patience for relationships to actual occasions. The relationships of _A_ to an actual occasion are simply how the eternal relationships of _A_ to other eternal objects are graded as to their realisation in that occasion. Thus the general principle which expresses _A’s_ ingression in the particular actual occasion α is the indeterminateness which stands in the essence of _A_ as to its ingression into α, and is the determinateness which stands in the essence of α as to the ingression of _Α_ into α. Thus the synthetic prehension, which is α, is the solution of the indeterminateness of _Α_ into the determinateness of α. Accordingly the relationship between _Α_ and α is external as regards _Α_, and is internal as regards α. Every actual occasion α is the solution of all modalities into actual categorical ingressions: truth and falsehood take the place of possibility. The complete ingression of _Α_ into α is expressed by all the true propositions which are about both _Α_ and α, and also—it may be—about other things. The determinate relatedness of the eternal object _Α_ to every other eternal object is how _Α_ is systematically and by the necessity of its nature related to every other eternal object. Such relatedness represents a possibility for realisation. But a relationship is a fact which concerns all the implicated relata, and cannot be isolated as if involving only one of the relata. Accordingly there is a general fact of systematic mutual relatedness which is inherent in the character of possibility. The realm of eternal objects is properly described as a ‘realm,’ because each eternal object has its status in this general systematic complex of mutual relatedness.