Featured on PDR in the essay The Uncertain Heavens: Christiaan Huygens’ Ideas of Extraterrestrial Life

During the 17th century, as knowledge of the Universe and its contents increased, so did speculation about life on other planets. One such source, as Hugh Aldersey-Williams explores, was Dutch astronomer, mathematician, and inventor Christiaan Huygens, whose earlier work on probability paved the way for his very modern evaluation of what alien life might look like.