(Population.)—7. And again: with regard to the proposition that the progress of population depends merely on the rate of wages, a very little observation of different communities, and of the same communities at different times, will show that this is a very rash and hasty generalization. When wages rise, whether or not population shall undergo a corresponding increase depends upon many other circumstances besides this single fact of the increase of wages. The effect of a rise of wages upon population is affected by the form of the wages, the time occupied by the change, the institutions of the society under consideration, and other causes: and a due classification of the conditions of the society according to these circumstances, is requisite in order to obtain any general proposition concerning the effect of a rise or fall of wages upon the progress of the population.
And thus those precepts of the philosophy of discovery which we have repeated so often, which are so simple, and which seem so obvious, have been neglected or violated in the outset of Political Economy as in so many other sciences:—namely, the precepts that we must classify our facts before we generalize, and seek for narrower generalizations and inductions before we aim at the widest. If these maxims had been obeyed, they would have saved the earlier speculators on this subject from some splendid errors; but, on the other hand, it may be said, that if these earlier speculators had not been thus bold, the science could not so soon have assumed that large and striking form which made it so attractive, and to which it probably owes a large part of its progress.
CHAPTER XXIV.
Modern German Philosophy[295].
I. Science is the Idealization of Facts.
1. I have spoken, a few chapters back, of the Reaction against the doctrines of the Sensational School in England and France. In Germany also there was a Reaction against these doctrines;—but there, this movement took a direction different from its direction in other countries. Omitting many other names, Kant, Fichte, Schelling and Hegel may be regarded as the writers who mark, in a prominent manner, this Germanic line of speculation. The problem of philosophy, in the way in which they conceived it, may best be explained by reference to that Fundamental Antithesis of which I had occasion to speak in the History of Scientific Ideas[296]. And in order to characterize the steps taken by these modern German philosophers, I must return to what I have said concerning the Fundamental Antithesis.
This Antithesis, as I have there remarked, is stated in various ways:—as the Antithesis of Thoughts and Things; of Ideas and Sensations; of Theory and Facts; of Necessary Truth and Experience; of the Subjective and Objective elements of our knowledge; and in other phrases. I have further remarked that the elements thus spoken of, though opposed, are inseparable. We cannot have the one without the other. We cannot have thoughts without thinking of Things: we cannot have things before us without thinking of them.
Further, it has been shown, I conceive, that our knowledge derives from the former of these two elements, namely our Ideas, its form and character of knowledge; our ideas being the necessary Forms of knowledge, while the Matter of our knowledge in each case is supplied by the appropriate perception or outward experience.
Thus our Ideas of Space and Time are the necessary Forms of our geometrical and arithmetical knowledge; and no sensations or experience are needed as the matter of such knowledge, except in so far as sensation and experience are needed to evoke our Ideas in any degree. And hence these sciences are sometimes called Formal sciences. All other Sciences involve, along with the experience and observation appropriate to each, a development of the ideal conditions of knowledge existing in our minds; and I have given the history, both of this development of ideas and of the matter derived from experience, in two former works, the History of Scientific Ideas, and the History of the Inductive Sciences. I have there traced this history through the whole body of the physical sciences.
But though Ideas and Perceptions are thus separate elements in our philosophy, they cannot in fact be distinguished and separated, but are different aspects of the same thing. And the only way in which we can approach to truth is by gradually and successively, in one instance after another, advancing from the perception to the idea; from the fact to the theory.