Concepts similar to those behind the metric system had been discussed in the 16th and 17th centuries. Simon Stevin had published his ideas for a decimal notation and John Wilkins had published a proposal for a decimal system of measurement based on natural units. The first practical realisation of the metric system came in 1799, during the French Revolution, when the existing system of measure, which had fallen into disrepute, was temporarily replaced by a decimal system based on the kilogram and the metre. The work of reforming the old system of weights and measures was sponsored by the revolutionary government, including the approval of Louis XVI before his fall from power. The metric system was to be, in the words of philosopher and mathematician Condorcet, "for all people for all time"