In the past few decades, European and American logicians have attempted to provide mathematical foundations for dialectical logic or argument.:201–372 There had been pre-formal and partially-formal treatises on argument and dialectic, from authors such as Stephen Toulmin (The Uses of Argument),:203–256 Nicholas Rescher (Dialectics),:330–336 and van Eemeren and Grootendorst (pragma-dialectics).:517–614 One can include the communities of informal logic and paraconsistent logic.:373–424 However, building on theories of defeasible reasoning (see John L. Pollock), systems have been built that define well-formedness of arguments, rules governing the process of introducing arguments based on fixed assumptions, and rules for shifting burden. Many of these logics appear in the special area of artificial intelligence and law, though the computer scientists' interest in formalizing dialectic originates in a desire to build decision support and computer-supported collaborative work systems.