In December 1639 the Pascal family left Paris to live in Rouen where Étienne had been appointed as a tax collector for Upper Normandy. Shortly after settling in Rouen, Blaise had his first work, Essay on Conic Sections published in February 1640.
Sa Disyembre 1639 ang Pascal pamilya kaliwa Paris sa manirahan sa Rouen kung saan Etienne had been hinirang bilang isang buwis para sa Upper Normandy. Makalipas ang ilang sandali-settle sa Rouen, Blaise had kanyang unang trabaho, magtangka sa alimusod Seksyon-publish sa Pebrero 1640.