It is in vain to look for a precise and exact _definition_ of the powers of Congress on several subjects. The Constitution does not undertake the task of making such exact definitions. In conferring powers, it proceeds by the way of _enumeration_, stating the powers conferred, one after another, in few words and where the power is general or complex in its nature, the extent of the grant must necessarily be judged of, and limited, by its object, and by the nature of the power. Few things are better known than the immediate causes which led to the adoption of the present Constitution; and there is nothing, as I think, clearer, than that the prevailing motive was _to regulate commerce_; to rescue it from the embarrassing and destructive consequences resulting from the legislation of so many different States, and to place it under the protection of a uniform law. The great objects were commerce and revenue; and they were objects indissolubly connected. By the Confederation, divers restrictions had been imposed on the States; but these had not been found sufficient. No State, it is true, could send or receive an embassy; nor make any treaty; nor enter into any compact with another State, or with a foreign power; nor lay duties interfering with treaties which had been entered into by Congress. But all these were found to be far short of what the actual condition of the country required. The States could still, each for itself, regulate commerce, and the consequence was a perpetual jarring and hostility of commercial regulation.