In those countries where nature is the most redundant in spontaneous produce the inhabitants will not be found the most remarkable for acuteness of intellect.
Necessity has been with great truth called the mother of invention.
Some of the noblest exertions of the human mind have been set in motion by the necessity of satisfying the wants of the body.

Want has not unfrequently given wings to the imagination of the poet, pointed the flowing periods of the historian, and added acuteness to the researches of the philosopher, and though there are undoubtedly many minds at present so far improved by the various excitements of knowledge, or of social sympathy, that they would not relapse into listlessness if their bodily stimulants were removed, yet it can scarcely be doubted that these stimulants could not be withdrawn from the mass of mankind without producing a general and fatal torpor, destructive of all the germs of future improvement.
Locke, if I recollect, says that the endeavour to avoid pain rather than the pursuit of pleasure is the great stimulus to action in life: and that in looking to any particular pleasure, we shall not be roused into action in order to obtain it, till the contemplation of it has continued so long as to amount to a sensation of pain or uneasiness under the absence of it.

To avoid evil and to pursue good seem to be the great duty and business of man, and this world appears to be peculiarly calculated to afford opportunity of the most unremitted exertion of this kind, and it is by this exertion, by these stimulants, that mind is formed.

If Locke's idea be just, and there is great reason to think that it is, evil seems to be necessary to create exertion, and exertion seems evidently necessary to create mind.
The necessity of food for the support of life gives rise, probably, to a greater quantity of exertion than any other want, bodily or mental.
The Supreme Being has ordained that the earth shall not produce good in great quantities till much preparatory labour and ingenuity has been exercised upon its surface.

There is no conceivable connection to our comprehensions, between the seed and the plant or tree that rises from it.