Few movements in the history of American politics and political thought have been of equal immediate or enduring importance with that associated with the name of Thomas Jefferson. And yet Jefferson never published anything other than very brief and inadequate discussions of the principles for which he stood. His only systematic exposition of his political ideas is found in his famous Notes on Virginia. This work, however, was written in 1781-82 and deals but remotely with the issues which were to occupy the stage after 1789. Neither in Jefferson's own writings nor in those of Madison and Monroe, his successors as official head of the Republican party and as president of the United States, do we find any adequate exposition of the theories associated with the era of Jeffersonian democracy. It is only in the extensive works of John Taylor of Caroline, a friend and associate of these men in the political battles of that period, that such an exposition is to be found. Jefferson wrote that “Colonel Taylor and myself have rarely, if ever, differed in any political principle of importance.” John Randolph said that Taylor's “disinterested principles” were “the only bond of union among Republicans.” And Timothy Pickering calls him “the Goliath of the party.” As Henry Adams has said, Taylor was regarded as a political thinker of the first rank by the Virginia school and by many other leaders of his time, but it is equally true that his writings have occupied a position of obscurity since his death. This obscurity, however, does not alter the fact that they were influential in their time and are today the best source of information concerning the principles of both the earlier and later phases of the movement initiated by Jefferson during the first years under the Constitution.