Despite considerable recent scholarly attention to the constitutional amending process, no contemporary work on the subject has analyzed the set of seven proposed amendments that Francis Lieber published in 1865, after circulating them in Congress the previous year. These proposals are important both because of Lieber's role in the founding of American political science and because of the manner in which Lieber justified change at a time when many had come to regard the Constitution as a sacred and untouchable document. Lieber was able to strike an appropriate balance between respect for the Constitution and a willingness to adapt it to change. Unlike some theorists who followed, Lieber further advocated an organic view of society, law, and Constitution, without undermining the importance of formal processes of change. There is circumstantial evidence that Lieber's proposals may have influenced the formation of the Thirteenth and Fourteenth, albeit not the Fifteenth, Amendment. As importantly, Lieber offered important justifications for formal amendment at a time when others were advocating extraconstitutional change. Because Lieber placed his proposals within a wider philosophical context, his justification for prudent use of the amending process continues to be relevant at a time when much different issues are on the national agenda.