The opening of Chapter II
INFLUENCE EXERCISED BY PHYSICAL LAWS OVER THE ORGANIZATION OF
SOCIETY AND OVER THE CHARACTER OF INDIVIDUALS.If we inquire what those physical agents are by which the human race is most powerfully influenced, we shall find that they may be classed under four heads: namely, Climate, Food, Soil, and the General Aspect of Nature; by which last, I mean those appearances which, though presented chiefly to the sight, have, through the medium of that or other senses, directed the association of ideas, and hence in different countries have given rise to different habits of national thought. To one of these four classes, may be referred all the external phenomena by which Man has been permanently affected. The last of these classes, or what I call the General Aspect of Nature, produces its principal results by exciting the imagination, and by suggesting those innumerable superstitions which are the great obstacles to advancing knowledge.