Rufus Wheeler Peckham, Addyston Pipe Steel Company v. United States…
“ If certain kinds of private contracts do directly, as already stated, limit or restrain, and hence regulate, interstate commerce, why should not the power of Congress reach those contracts just the same as if the legislation of some state had enacted the provisions contained in them? The private contracts may in truth be as far reaching in their effect upon interstate commerce as would the legislation of a single state of the same character. ”
