To use another illustration: If the discharge of a shot frightens some birds, this effect is due to the combined action of the shot and the timidity of the birds. If the majority of the birds fly away, the shot will be considered as the cause. But if the minority fly away, their timidity will be regarded as the cause. Effects are subsequences. Since all things in nature follow other things and all things have an antecedent and a subsequent, we may call the natural, the real, the sense perceptions absolute effects, having no cause unless we find one with our faculty of thought by systematizing the given material. Causes are mental generalizations of perceptible changes. The supposed relation of cause and effect is a miracle, a creation of something out of nothing. For this reason this relation has been and still is an object of speculative reasoning. The speculative cause creates its effects. But in reality the effects are the material out of which the brain, or science, forms its causes. The cause concept is a product of reason; not of "pure" reason, but of reason married to the world of sense perceptions. If Kant maintains that the statement: "Every change has its cause" is an _a priori truth_ which we cannot experience because no one can possibly experience all changes, although every one has the irrefutable feeling of the correctness of this statement, we know now that this statement expresses merely the experience that the phenomenon which we call reason recognizes the uniform element in all multiformity. Or in other words, we now know that the development of the general element out of the concrete facts is called reason, thought, or mind. The secure knowledge that every change has its cause is nothing else but the conviction that we are thinking human beings. _Cogito, ergo sum._ I think, therefore I am. We have experienced the nature of our reason instinctively even if we have not analyzed it scientifically. We are as well aware of the faculty of our reason to abstract a cause out of every given change, as we are that every circle is round, that a is equal to a. We know that the general is the product of reason, and reason produces this general thing in contact with every given object. And since all objects before and after a certain other object are temporal changes, it follows that all changes which we as thinking beings experience must have a general antecedent, a cause.