"Of all the Acts that have ever been passed by Parliament, the Toleration Act is perhaps that which most strikingly illustrates the peculiar vices and the peculiar excellences of English legislation. The science of Politics bears in one respect a close analogy to the science of Mechanics. The mathematician can easily demonstrate that a certain power, applied by means of a certain lever or of a certain system of pulleys, will suffice to raise a certain weight. But his demonstration proceeds on the supposition that the machinery is such as no load will bend or break. If the engineer, who has to lift a great mass of real granite by the instrumentality of real timber and real hemp, should absolutely rely on the propositions which he finds in treatises on Dynamics, and should make no allowance for the imperfection of his materials, his whole apparatus of beams, wheels, and ropes would soon come down in ruin, and, with all his geometrical skill, he would be found a far inferior builder to those painted barbarians who, though they never heard of the parallelogram of forces, managed to pile up Stonehenge. What the engineer is to the mathematician, the active statesman is to the contemplative statesman. It is indeed most important that legislators and administrators should be versed in the philosophy of government, as it is most important that the architect who has to fix an obelisk on its pedestal, or to hang a tubular bridge over an estuary, should be versed in the philosophy of equilibrium and motion. But, as he who has actually to build must bear in mind many things never noticed by D'Alembert and Euler, so must he who has actually to govern be perpetually guided by considerations to which no allusion can be found in the writings of Adam Smith or Jeremy Bentham. The perfect law-giver is a just temper between the mere man of theory, who can see nothing but general principles, and the mere man of business, who can see nothing but particular circumstances. Of law-givers, in whom the speculative element has prevailed to the exclusion of the practical, the world has during the last eighty years been singularly fruitful. To their wisdom Europe and America have owed scores of abortive constitutions, scores of constitutions which have lived just long enough to make a miserable noise, and have then gone off in convulsions. But in English legislation the practical element has always predominated, and not seldom unduly predominated, over the speculative. To think nothing of symmetry and much of convenience; never to remove an anomaly merely because it is an anomaly; never to innovate except when some grievance is felt; never to innovate except so far as to get rid of the grievance; never to lay down any proposition of wider extent than the particular case for which it is necessary to provide; these are the rules which have, from the age of John to the age of Victoria, generally guided the deliberations of our two hundred and fifty Parliaments."[321]