Other scholars, such as Robert H. Bork and Daniel E. Troy, argue that prior to 1887, the Commerce Clause was rarely invoked by Congress and so a broad interpretation of the word "commerce" was clearly never intended by the Founding Fathers. In support of that claim, they argue that the word "commerce," as used in the Constitutional Convention and the Federalist Papers, can be substituted with either "trade" or "exchange" interchangeably and still preserve the meaning of those statements. They also point to James Madison's statement in an 1828 letter that the "Constitution vests in Congress expressly... 'the power to regulate trade'."