When a subject is broken off, I shall render my transitions as gradual as I can, by still preserving some chain of connexion; and although I cannot flatter myself (in such infinite variety of choice, as to order and distribution) to hit off, at all times, that method, which may appear to every reader the most natural and the most correct, yet I shall spare no pains in casting the materials into different forms, so as to make the best distribution of them in my power. ------------------------------------------------------------------------ CHAP. III. _Upon what Principles, and from what_ natural Causes _do Mankind multiply? And what are the effects of Procreation in Countries where Numbers are not found to increase?_ The multiplication of mankind has been treated of in different ways; some have made out tables to shew the progression of multiplications, others have treated the question historically. The state of numbers in different ages of the world, or in different countries at different times, has been made the object of inquiry; and the most exact scrutiny into antient authors, the means of investigating the truth of this matter. All passages relative to the subject have been laid together, and accompanied with glosses and interpretations the most plausible, in order to determine the main question. The elaborate performances of Mr. Hume, and Mr. Wallace, who have adopted opposite opinions in regard to the populousness of the antient world, have left nothing new to be said upon this subject; at least the application they appear to have given in examining the antients, is a great discouragement to any one who might otherwise still flatter himself, there, to find out circumstances proper to cast a new light upon the question. My intention in this chapter is not to decide, nor even to give my opinion upon that matter, far less to combat the arguments advanced on either side. I am to consider the question under a different point of view; not to enquire what numbers of people were found upon the earth at a certain time, but to examine the natural and rational causes of multiplication. If we can discover these, we may perhaps be led to judge how far they might have operated in different ages and in different countries.