The framers were (mostly) lawyers, and wrote the document against the background of English common law: http://www.libertylawsite.org/liberty-forum/why-you-cant-und....
Exceptions to the "freedom of speech" are part of the Constitution, despite not being written in so many words, for the same reason "due process" requires a presumption of innocence, even though the latter phrase appears nowhere in the document.
The framers were (mostly) lawyers, and wrote the document against the background of English common law: http://www.libertylawsite.org/liberty-forum/why-you-cant-und....
Exceptions to the "freedom of speech" are part of the Constitution, despite not being written in so many words, for the same reason "due process" requires a presumption of innocence, even though the latter phrase appears nowhere in the document.