John Law ( baptized 21 April 1671 - 21 March 1729 ) was a Scottish economist who believed that money was only a means of exchange that did not have wealth in itself , and that national wealth depended on trade . John Law ( baptised 21 April 1671 â `` died 21 March 1729 ) was a Scottish economist who believed that money was only a means of exchange that did not constitute wealth in itself and that national wealth depended on trade .