That the temper of the heart, and the intellectual operations of the mind, are, in some measure, dependent on the state of the animal organs, is well known from experience. Men differ from themselves in sickness and in health; under a change of diet, of air, and of exercise: but we are, even in these familiar instances, at a loss how to connect the cause with its supposed effect: and though climate, by including a variety of such causes, may, by some regular influence, affect the characters of men, we can never hope to explain the manner of those influences till we have understood, what probably we shall never understand, the structure of those finer organs with which the operations of the soul are connected. When we point out, in the situation of a people, circumstances which, by determining their pursuits, regulate their habits, and their manner of life; and when, instead of referring to the supposed physical source of their dispositions, we assign their inducements to a determinate conduct; in this we speak of effects and of causes whose connection is more familiarly known. We can understand, for instance, why a race of men like the Samoiede, confined, during great part of the year, to darkness, or retired into caverns, should differ in their manners and apprehensions from those who are at liberty in every season; or who, instead of seeking relief from the extremities of cold, are employed in search of precautions against the oppressions of a burning sun. Fire and exercise are the remedies of cold; repose and shade the securities from heat. The Hollander is laborious and industrious in Europe; he becomes more languid and slothful in India. [Footnote: The Dutch sailors, who were employed in the siege of Malaco, tore or burnt the sail cloth which was given them to make tents, that they might not have the trouble of making or pitching them. _Voy. de Matelief._] Great extremities, either of heat or cold, are perhaps, in a moral view, equally unfavourable to the active genius of mankind, and by presenting alike insuperable difficulties to be overcome, or strong inducements to indolence and sloth, equally prevent the first applications of ingenuity, or limit their progress. Some intermediate degrees of inconvenience in the situation, at once excite the spirit, and, with the hopes of success, encourage its efforts. "It Is in the least favourable situations," says Mr. Rousseau, "that the arts have flourished the most. I could show them in Egypt, as they spread with the overflowing of the Nile; and in Attica, as they mounted up to the clouds, from a rocky soil and from barren sands; while on the fertile banks of the Eurotas, they were not able to fasten their roots."