I hold that to be necessary and to be the consequent of a given reason are absolutely interchangeable notions, and completely identical. We can never know, nor even think, anything as necessary, except so far as we regard it as the consequent of a given reason; and the conception of necessity contains absolutely nothing more than this dependence, this being established through something else, and this inevitable following from it. Thus it arises and exists simply and solely through the application of the principle of sufficient reason. Therefore, there is, according to the different forms of this principle, a physical necessity (the effect from the cause), a logical (through the ground of knowing, in analytical judgments, syllogisms, &c.), a mathematical (according to the ground of being in time and space), and finally a practical necessity, by which we intend to signify not determination through a pretended categorical imperative, but the necessary occurrence of an action according to the motives presented, in the case of a given empirical character. But everything necessary is only so relatively, that is, under the presupposition of the reason from which it follows; therefore absolute necessity is a contradiction. With regard to the rest, I refer to § 49 of the essay on the principle of sufficient reason. The contradictory opposite, _i.e._, the denial of necessity, is _contingency_. The content of this conception is, therefore, negative—nothing more than this: absence of the connection expressed by the principle of sufficient reason. Consequently the contingent is also always merely relative. It is contingent in relation to something which is not its reason. Every object, of whatever kind it may be—for example, every event in the actual world—is always at once necessary and contingent, _necessary_ in relation to the _one_ condition which is its cause: _contingent_ in relation to everything else. For its contact in time and space with everything else is a mere coincidence without necessary connection: hence also the words chance, συμπτωμα, _contingens_. Therefore an absolute contingency is just as inconceivable as an absolute necessity. For the former would be simply an object which stood to no other in the relation of consequent to its reason. But the inconceivability of such a thing is just the content of the principle of sufficient reason negatively expressed, and therefore this principle must first be upset before we can think an absolute contingency; and even then it itself would have lost all significance, for the conception of contingency has meaning only in relation to that principle, and signifies that two objects do not stand to each other in the relation of reason and consequent.