It is obvious that the texture of constitutional law has changed radically in the course of American history; yet the text of the Constitution itself has been extremely durable, not to say sluggish. The leading cases of modern constitutional law are or pretend to be "interpretations" or glosses on the post-civil war amendments, which have not been altered in over a century; the bill of rights;or the text of the original Constitution, which is now some two centuries old. A scholar of 1870 or 1880 who woke from a century's sleep would simply not recognize today's body of constitutional doctrine; current equal protection doctrine, for example, would be totally beyond his or her comprehension. Yet much of the standard work on both constitutional theory and constitutional history has a strongly normative flavor, and it fails to come to grips with the powerful forces that have turned old doctrines topsyturvy and pulled new doctrines into existence like rabbits from a magician's hat.