4. Huygens’ Stay in Paris

When the successor of Frederick Henry, Prince William II of Orange, died at a young age, in 1650, the western provinces of the Republic (whose independence from Spain had recently been officially recognized at the Peace of Westphalia) decided they no longer needed a stadtholder as military leader. The followers and officials of the House of Orange were therefore pushed aside, and this meant that the influence of father Constantijn Huygens diminished drastically. He could thus do little to help his sons obtain suitable high office. Christiaan, therefore, remained without an income-producing position, but because the family was sufficiently rich, he could now actually devote himself fully to his beloved studies.

In 1655, Christiaan went on a voyage to Paris, accompanied by his younger brother Lodewijk and two of their cousins. In those days, such a journey was a customary way for young men of well-to-do families to round off their education. They saw something of the world and learned the customs of foreign lands and courts. They also formed acquaintances with nobles, statesmen and other influential people in other parts of Europe, ties that would be useful to them in their later careers.

Christiaan not only spent his time visiting curiosities and paying courtesy visits: in Paris he made the acquaintance of the most important mathematicians of France and participated in the salon discussions about the new discoveries that were made in science. He formed a friendship with the poet Jean Chapelain and with the astronomer Ismael Boulliau. It was probably at this time that his decision to seek fulfilment in his life in science, and not in administration or belles lettres became fixed.