of grass that we
see), a general and fatal torpor of the human faculties would probably
ensue; even the bodily wants of mankind would cease to stimulate them
to exertion, could they not reasonably expect that if their efforts
were well directed they would be crowned with success. The constancy of
the laws of nature is the foundation of the industry and foresight of
the husbandman, the indefatigable ingenuity of the artificer, the
skilful researches of the physician and anatomist, and the watchful
observation and patient investigation of the natural philosopher. To
this constancy we owe all the greatest and noblest efforts of
intellect. To this constancy we owe the immortal mind of a Newton.

As the reasons, therefore, for the constancy of the laws of nature
seem, even to our understandings, obvious and striking; if we return to
the principle of population and consider man as he really is, inert,
sluggish, and averse from labour, unless compelled by necessity (and it
is surely the height of folly to talk of man, according to our crude
fancies of what he might be), we may pronounce with certainty that the
world would not have been peopled, but for the superiority of the power
of population to the means of subsistence. Strong and constantly
operative as this stimulus is on man to urge him to the cultivation of
the earth, if we still see that cultivation proceeds very slowly, we
may fairly conclude that a less stimulus would have been insufficient.
Even under the operation of this constant excitement, savages will
inhabit countries of the greatest natural fertility for a long period
before they betake themselves to pasturage or agriculture. Had
population and food increased in the same ratio, it is probable that
man might never have emerged from the savage state. But supposing the
earth once well peopled, an Alexander, a Julius Caesar, a Tamberlane,
or a bloody revolution might irrecoverably thin the human race, and
defeat the great designs of the Creator. The ravages of a contagious
disorder would be felt for ages; and an earthquake might unpeople a
region for ever. The principle, according to which population
increases, prevents the vices of mankind, or the accidents of nature,
the partial evils arising from general laws, from obstructing the high
purpose of the creation. It keeps the inhabitants of the earth always
fully up to the level of the means of subsistence; and is constantly
acting upon man as a powerful stimulus