CHAPTER 4.
State of civilized nations--Probability that Europe is much more populous now than in the time of Julius Caesar--Best criterion of population--Probable error of Hume in one the criterions that he proposes as assisting in an estimate of population--Slow increase of population at present in most of the states of Europe--The two principal checks to population--The first, or preventive check examined with regard to England.
In examining the next state of mankind with relation to the question before us, the state of mixed pasture and tillage, in which with some variation in the proportions the most civilized nations must always remain, we shall be assisted in our review by what we daily see around us, by actual experience, by facts that come within the scope of every man's observation.
Notwithstanding the exaggerations of some old historians, there can remain no doubt in the mind of any thinking man that the population of the principal countries of Europe, France, England, Germany, Russia, Poland, Sweden, and Denmark is much greater than ever it was in former times.

The obvious reason of these exaggerations is the formidable aspect that even a thinly peopled nation must have, when collected together and moving all at once in search of fresh seats.

If to this tremendous appearance be added a succession at certain intervals of similar emigrations, we shall not be much surprised that the fears of the timid nations of the South represented the North as a region absolutely swarming with human beings.

A nearer and juster view of the subject at present enables us to see that the inference was as absurd as if a man in this country, who was continually meeting on the road droves of cattle from Wales and the North, was immediately to conclude that these countries were the most productive of all the parts of the kingdom.
The reason that the greater part of Europe is more populous now than it was in former times, is that the industry of the inhabitants has made these countries produce a greater quantity of human subsistence.

For I conceive that it may be laid down as a position not to be controverted, that, taking a sufficient extent of territory to include within it exportation and importation, and allowing some variation for the prevalence of luxury, or of frugal habits, that population constantly bears a regular proportion to the food that the earth is made to produce.