In our reasonings concerning matter of fact, there are all imaginable degrees of assurance, from the highest certainty to the lowest species of moral… - David Hume

Were a stranger to drop on a sudden into this world, I would show him, as a specimen of its ills, a hospital full of diseases, a prison crowded with malefactors and debtors, a field of battle strewed with carcasses, a fleet foundering in the ocean, a nation languishing under tyranny, famine, or pestilence. To turn the gay side of life to him, and give him a notion of its pleasures; whither should I conduct him? to a ball, to an opera, to court? He might justly think, that I was only showing him a diversity of distress and sorrow.

But though all the general rules of art are founded only on experience and on the observation of the common sentiments of human nature, we must not imagine, that, on every occasion, the feelings of men will be conformable to these rules.

Your corn is ripe today; mine will be so tomorrow. 'Tis profitable for us both, that I should labour with you today, and that you should aid me tomorrow. I have no kindness for you, and know you have as little for me. I will not, therefore, take any pains upon your account; and should I labour with you upon my own account, in expectation of a return, I know I should be disappointed, and that I should in vain depend upon your gratitude. Here then I leave you to labour alone; You treat me in the same manner. The seasons change; and both of us lose our harvests for want of mutual confidence and security.