the preamble to the united states constitution is a brief introduction to the constitution's purposes and guiding principles. it provides the founding fathers' intentions for creating the constitution and what they hoped the constitution would achieve. it was added to the constitution as an afterthought and was not discussed on the floor of the constitutional convention nor was it voted on. gouverneur morris, one of the writers of the constitution, wrote and added it at the last moment. the preamble itself did not have any legal meaning. the supreme court upheld this view in "jacobson v. massachusetts" (1905).