He belonged to the old guard of economists who believed that economic prosperity cannot be attained by printing money. This was indeed going against the popular tides of the late 1930s and 1940s. At that time, Keynesianism had been accepted by the mainstream economists on both sides of the Atlantic as a new religion. It explicitly advocated the desirability of deficit financing as a strategy for attaining full employment. Exter doubted the validity of this claim both in his public speeches and writings. At one stage, even Paul Samuelson had teased him that ‘though Exter may be right, he was lonely in his opinion’. The fact that there were no supporters for his view did not prevent Exter from making public what he believed to be true. On the very first day of the establishment of the Central Bank of Ceylon, in a press interview he gave as the first Governor of the Bank, he warned against the use of the Bank for things which it cannot fulfill. “Today, we can only be filled with high hopes for the future. It would be a mistake to expect startling results immediately from the establishment of the Central Bank. There is no financial wizardry by which the Bank can suddenly pull out of a hat a higher standard of living for everybody. The Bank’s contribution must necessarily be a long-run contribution. The Bank does not itself produce goods and services, but it should, by creating the right monetary conditions enable the country…” to do so.
It is from there that he came to Ceylon as the consultant on the establishment of a central bank, still on release from the Federal Reserve System. After serving his term as Governor of the Central Bank, Exter did not return to the Federal Reserve System. Instead, in 1953, he joined the World Bank and was offered the position of the division chief for the Middle East. After a year with the World Bank, he came back to the Federal Reserve System as its Vice President on international operations at the Federal Reserve Bank of New York. His career at the Federal Reserve System ended in 1959 when he decided to join the First National City Bank which later became the Citibank. From 1960 to 1972, he was the Senior Vice President of the Citibank in charge of its relations with foreign central banks and governments. With a huge fortune made on the  BIS Review 20/2007  1  gold market by using his own expertise on the foresight of irresponsible central banking and its inevitable consequences, Exter took an early retirement in 1972 and went into private consultancy work. According to his own admission, the prospect for his fortune on gold dawned on him after a friendly debate he had in 1962 with his one time Harvard buddy and Nobel Laureate Paul Samuelson. In that debate on why the dollar was becoming weak and USA was losing gold, Exter gave his diagnosis which was based on his experience with the Federal Reserve System.