I confess that there are several parts of this Constitution which I do not at present approve, but I am not sure I shall never approve them. For having lived long, I have experienced many instances of being obliged by better information, or fuller consideration, to change opinions even on important subjects, which I once thought right, but found to be otherwise.

Speech in the Constitutional Convention, Philadelphia, Pennsylvania (September 17, 1787); reported in James Madison, Journal of the Federal Convention, ed. E. H. Scott (1893), p. 741