A hopeful note was expounded 250 years ago by Lord Mansfield when he stated that “mercantile law … is the same all over the world. For from the same premises, the sound conclusions of reason and justice must universally be the same.” The universality of commerical practice provides the opportunity to structure a uniform law of sales premised upon the commonality of practice. It is on this view of the universality of commercial practice that the success of a uniform international sales law is hinged. Critics of such a view assert that such uniformity efforts are both unwise and doomed to failure. Unwise, because there are substantial and reasonable differences in national practices that are reflected in differences in national laws. Doomed to failure, because legal and cultural differences will necessarily be reflected in the national courts' interpretations of a supranational sales law. Thus, the uniformity of form (a single body of rules) will lose to non-uniform application (jurisprudential chaos). A middle view between Mansfield's idealism and the realist critque will be discussed later in this chapter.