The subversion of a government, to deserve any praise, must be considered but as a step preparatory to the formation of something better, either in the scheme of the government itself, or in the persons who administer it, or in both.  These events cannot in reason be separated.  For instance, when we praise our Revolution of 1688, though the nation in that act was on the defensive, and was justified in incurring all the evils of a defensive war, we do not rest there.  We always combine with the subversion of the old government the happy settlement which followed.  When we estimate that Revolution, we mean to comprehend in our calculation both the value of the thing parted with and the value of the thing received in exchange.

The burden of proof lies heavily on those who tear to pieces the whole frame and contexture of their country, that they could find no other way of settling a government fit to obtain its rational ends, except that which they have pursued by means unfavorable to all the present happiness of millions of people, and to the utter ruin of several hundreds of thousands.  In their political arrangements, men have no right to put the well-being of the present generation wholly out of the question.  Perhaps the only moral trust with any certainty in our hands is the care of our own time.  With regard to futurity, we are to treat it like a ward.  We are not so to attempt an improvement of his fortune as to put the capital of his estate to any hazard.

It is not worth our while to discuss, like sophisters, whether in no case some evil for the sake of some benefit is to be tolerated.  Nothing universal can be rationally affirmed on any moral or any political subject.  Pure metaphysical abstraction does not belong to these matters.  The lines of morality are not like the ideal lines of mathematics.  They are broad and deep as well as long.  They admit of exceptions; they demand modifications.  These exceptions and modifications are not made by the process of logic, but by the rules of prudence.  Prudence is not only the first in rank of the virtues political and moral, but she is the director, the regulator, the standard of them all.  Metaphysics cannot live without definition; but Prudence is cautious how she defines.  Our courts cannot be more fearful in suffering fictitious cases to be brought before them for eliciting their determination on a point of law than prudent moralists are in putting extreme and hazardous cases of conscience upon emergencies not existing.  Without attempting, therefore, to define, what never can be defined, the case of a revolution in government, this, I think, may be safely affirmed,—­that a sore and pressing evil is to be removed, and that a good, great in its amount and unequivocal in its nature, must be probable almost to certainty, before the inestimable price of our own morals and the well-being of a number of our fellow-citizens is paid for a revolution.  If ever we ought to be economists even to parsimony, it is in the voluntary production of evil.  Every revolution contains in it something of evil.