Imagine what a condition a science must be in, when as yet there shall be no such thing as forming any extensive proposition relative to it, that shall be at the same time a true one: where, if the proposition shall be true of some of the particulars contained under it, it shall be false with regard to others. What a state would botany, for example, be in, if the classes were so contrived, that no common characters could be found for them? Yet in this state, and no better, seems every system of penal law to be, authoritative or unauthoritative, that has ever yet appeared. Try if it be otherwise, for instance, with the delicta privata et publica, and with the publica ordinaria, and publica extra-ordirnaria of the Roman law. All this for want of method: and hence the necessity of endeavouring to strike out a new one.
Nor is this want of method to be wondered at. A science so new as that of penal legislation, could hardly have been in any better state. Till objects are distinguished, they cannot be arranged. It is thus that truth and order go on hand in hand. It is only in proportion as the former is discovered, that the latter can be improved. Before a certain order is established, truth can be but imperfectly announced: but until a certain proportion of truth has been developed and brought to light, that order cannot be established. The discovery of truth leads to the establishment of order: and the establishment of order fixes and propagates the discovery of truth.
IPML Chapter 16 Section 4