Switcheroo Theories, Real and Imagined

       Polar shifts in politics only occur when extreme changes in the practice of politics make the foundational principles of the party outdated.
       The actual switcheroo came in Nineteenth-Century Britain, where Benjamin Disraeli turned Toryism from an ideology that gave unlimited power to the Crown into a Conservative party.  Eighteenth-Century Tories were unremittingly hostile to commercial life, and considered landed gentry the only fit wealthy.  Disraeli romanticized pre-Reformation England, and had Charles I in his pantheon of Tory saints.  Old Tory ideology was about King over Parliament;  new Tory ideology was a rejection of Utilitarian attempts at utopia.
       The imaginary switcheroo came in Nineteenth or Twentieth-Century America.  The Republican Party, after opposing extension of slavery, the Dred Scott decision that black people were farm animals, and secession, supposedly changed place with the pro-slavery Democratic Party.  Perhaps it was after Charles Sumner authored the 13th, 14th, and 15th Amendments.  It must have been after a Democratic president thought "Birth of a Nation" was a great film, and re-segregated the military.  As a matter of fact, black Americans were reliably Republican until FDR's presidency.
       Unlike the actual switcheroo, there was a genuine political change that caused Toryism to become Conservative (and Whig to become Labour).  The Reform Act of 1835 made more Britons entitled to vote.  This, combined with post-1688 Parliamentary ascendency made the Toryism of Henry St. John and Jonathan Swift an antique curiosity.  Republican ideology, being a continuation of old Federalist principles, has never been obsolete.

Why Systematizers Are Wrong, Part Three

"In short, my lord, all these systems are so many enchanted castles, they appear to be something, they are nothing but appearances: like them too, dissolve the charm, and they vanish from the sight(p9). The philosopher begins with reason and ends with imagination. The historian inverts this order: he begins without memorials and he sometimes ends with them (p70)."
Henry St. John (Viscount Bolingbroke)
Study and Use of History

Why Systematizers Are Wrong, Part Two

"Metaphysical hypotheses, in short, are not content to account for what may be by what is, nor to improve science according to the conditions of our nature, by raising probability on the foundations of certainty: but the makers of them affect to range in the immense void of possibility, with little or no regard to actuality; and begin very often, as well as end, in supposition(p360)."
Fourth Essay
Henry St. John (Viscount Bolingbroke)

Why Systematizers Are Wrong

"Thus we may concieve how men came to employ corporeal ideas, for the most part to explain the intellectual phaenomena, and sometimes to assist even their own reflections on them. The art was reasonably invented and usefully applied. But it soon became artifice, as soon as philosophers took into their heads to affect such science as they are incapable of attaining(p 131). Figures in general, these of speech, and all others that do not typify determinatly, are unworthy of rational creatures, how much more of God? and figures that typify nothing, are nothing, or they are worse than nothing; they are so many lies, since they pretend to denote something real, where nothing real exists (p138)."

Concerning the Nature, Extent, and Reality of Human
Knowledge
Henry St. John (Viscount Bolingbroke)