Why be just? The problem of the fool
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The problem of the fool stated.
The fool hath said in his heart, there is no such thing as justice, and sometimes also with his tongue, seriously alleging that every man's conservation and contentment being committed to his own care, there could be no reason why every man might not do what he thought conduced thereunto: and therefore also to make, or not make; keep, or not keep, covenants was not against reason when it conduced to one's benefit. He does not therein deny that there be covenants; and that they are sometimes broken, sometimes kept; and that such breach of them may be called injustice, and the observance of them justice: but he questioneth whether injustice, taking away the fear of God (for the same fool hath said in his heart there is no God), not sometimes stand with that reason which dictateth to every man his own good; and particularly then, when it conduceth to such a benefit as shall put a man in a condition to neglect not only the dispraise and revilings, but also the power of other men. The kingdom of God is gotten by violence: but what if it could be gotten by unjust violence? Were it against reason so to get it, when it is impossible to receive hurt by it? And if it be not against reason, it is not against justice: or else justice is not to be approved for good. From such reasoning as this, successful wickedness hath obtained the name of virtue: and some that in all other things have disallowed the violation of faith, yet have allowed it when it is for the getting of a kingdom. And the heathen that believed that Saturn was deposed by his son Jupiter believed nevertheless the same Jupiter to be the avenger of injustice, somewhat like to a piece of law in Coke's Commentaries on Littleton; where he says if the right heir of the crown be attainted of treason, yet the crown shall descend to him, and eo instante the attainder be void: from which instances a man will be very prone to infer that when the heir apparent of a kingdom shall kill him that is in possession, though his father, you may call it injustice, or by what other name you will; yet it can never be against reason, seeing all the voluntary actions of men tend to the benefit of themselves; and those actions are most reasonable that conduce most to their ends. This specious reasoning is nevertheless false.
Hobbes, Lev XV 4
To the problem of the fool.
For the question is not of promises mutual, where there is no security of performance on either side, as when there is no civil power erected over the parties promising; for such promises are no covenants: but either where one of the parties has performed already, or where there is a power to make him perform, there is the question whether it be against reason; that is, against the benefit of the other to perform, or not. And I say it is not against reason. For the manifestation whereof we are to consider; first, that when a man doth a thing, which notwithstanding anything can be foreseen and reckoned on tendeth to his own destruction, howsoever some accident, which he could not expect, arriving may turn it to his benefit; yet such events do not make it reasonably or wisely done. Secondly, that in a condition of war, wherein every man to every man, for want of a common power to keep them all in awe, is an enemy, there is no man can hope by his own strength, or wit, to himself from destruction without the help of confederates; where every one expects the same defence by the confederation that any one else does: and therefore he which declares he thinks it reason to deceive those that help him can in reason expect no other means of safety than what can be had from his own single power. He, therefore, that breaketh his covenant, and consequently declareth that he thinks he may with reason do so, cannot be received into any society that unite themselves for peace and defence but by the error of them that receive him; nor when he is received be retained in it without seeing the danger of their error; which errors a man cannot reasonably reckon upon as the means of his security: and therefore if he be left, or cast out of society, he perisheth; and if he live in society, it is by the errors of other men, which he could not foresee nor reckon upon, and consequently against the reason of his preservation; and so, as all men that contribute not to his destruction forbear him only out of ignorance of what is good for themselves.
As for the instance of gaining the secure and perpetual felicity of heaven by any way, it is frivolous; there being but one way imaginable, and that is not breaking, but keeping of covenant.
And for the other instance of attaining sovereignty by rebellion; it is manifest that, though the event follow, yet because it cannot reasonably be expected, but rather the contrary, and because by gaining it so, others are taught to gain the same in like manner, the attempt thereof is against reason. Justice therefore, that is to say, keeping of covenant, is a rule of reason by which we are forbidden to do anything destructive to our life, and consequently a law of nature.
Hobbes, Lev XV 5-7