3 Central banks cannot substitute for stringent carbon pricing But problems arise when monetary policy, financial supervision or banking regulation are pressed into service for other purposes. Each of these domains already has a clearly defined objective. This focus is also consistent with the Tinbergen rule, named after the first Nobel Laureate in economics, Jan Tinbergen.
His rule stipulates that for each separate economic policy target, there must also be at least one separate instrument. 3/3  BIS central bankers' speeches