Page:An Essay on the Principle of Population (1798).djvu/194

168 of the same size that would support as large a head as a cabbage.

The reasons of the mortality of plants are at present perfectly unknown to us. No man can say why such a plant is annual, another biennial, and another endures for ages. The whole affair in all these cases, in plants, animals, and in the human race, is an affair of experience; and I only conclude that man is mortal because the invariable experience of all ages has proved the mortality of those materials of which his visible body is made.

"What can we reason, but from what we know?"

Sound philosophy will not authorize me to alter this opinion of the mortality of man on earth, till it can be clearly proved, that the human race has