not only is it the general interest that crimes should not be committed, but that they should be rare in proportion to the evils they cause to society. the more opposed therefore that crimes are to the public welfare, and the more numerous the incentives to them, the stronger should be the repellent obstacles. this principle accordingly establishes the necessity of a certain proportion between crimes and punishments.

if pleasure and pain are the motors of sensitive beings, if the invisible lawgiver of humanity has decreed rewards and punishments as one of the motives to impel men to even their noblest endeavours, the inexact distribution of these motives will give rise to that contradiction, as little noticed as it is of common occurrence, namely, that the laws punish crimes which are entirely of their own creation. if an equal penalty is attached to two crimes of unequal injury to society, the greater crime of the two, if it promise a greater advantage than the other, will have no stronger motive in restraint of its perpetration.[197] whoever, for example, sees the same punishment of death decreed for the man who kills a pheasant and the man who slays his fellow or falsifies an important document, will draw no distinction between such crimes; and thus moral sentiments, the product only of many ages and of much bloodshed, the slowest and most difficult attainment of the human mind, dependent, it has been thought, on the aid of the most sublime motives and on a parade of the gravest formalities, will be destroyed and lost.

it is impossible to prevent all the disorders that may arise in the universal conflict of human passions. their increase depends on that of population and on the crossings of private interests, which cannot be directed with geometrical exactness to the public welfare. in political arithmetic the calculation of probabilities must be substituted for mathematical exactness. glance at the history of the world, and you will see disorders increase with the increase of the bounds of empire; thus national feeling being to the same extent diminished, the general inducement to crime increases with the greater interest of each individual in such disorders, and on this account the necessity for aggravating penalties ever continues to increase.

that force, similar to the force of gravitation, which constrains us to seek our own well-being, only admits of counteraction in proportion to the obstacles[198] opposed to it. the effects of this force make up the confused series of human actions; if these clash together and impede one another, punishments, which i would call political obstacles, prevent bad effects from resulting, without destroying the impelling cause, which lies in the sensibility inseparable from humanity; and the legislator, in enacting them, acts the part of a clever architect, whose function it is to counteract the tendency of gravitation to cause a building to fall, and to bring to bear all the lines which contribute to its strength.

given the necessity of the aggregation of mankind, and given the covenants which necessarily result from the very opposition of private interests, a scale of offences may be traced, beginning with those which tend directly to the destruction of society, and ending with acts of the smallest possible injustice committed against individual members of it. between these extremes are comprised all the actions opposed to the public welfare which are called crimes, and which by imperceptible degrees decrease in enormity from the highest to the lowest. if the infinite and obscure combinations of human actions admitted of mathematical treatment, there ought to be a corresponding scale of punishments, varying from the severest to the slightest penalty. if there were an exact and universal scale of crimes and punishments, we should have an approximate and general test by[199] which to gauge the degrees of tyranny and liberty in different governments, the relative state of the humanity or wickedness of different nations. but the wise legislator will rest satisfied with marking out the principal divisions in such a scale, so as not to invert their order, nor to affix to crimes of the first degree punishments due to those of the last.