He received the degree of Doctor of Laws at Orleans (France).
He became pensionary (chief magistrate) of Delft in 1679, after having practiced there as an attorney.
In 1682 William III of Orange sent him as ambassador to the French court.
There he gained a keen insight into the policies of Louis XIV and returned a firm supporter of the house of Orange.
At the insistence of William, he accepted the post of grand pensionary (prime minister) on May 26, 1689, after having served in that capacity as a temporary functionary.
He showed great activity, intelligence, and diplomatic tact, but lacked sufficient self-assurance and persistence, becoming hesitant and afraid of responsibility, especially after the death of the King-Stadholder William III in 1702.
He continued the old policy too long and did not understand England's purpose in the War of the Spanish Succession.