 After his first visit to Paris and the criticism that ensued, in 1290 Llull starts to make profound changes that will lead him to reformulate the Ars. The Ars generalis ultima, written between 1305 and 1308, and the Ars brevis, from 1308, establish the most accomplished formulations of this new version of Llull’s tool. The changes he introduced to the Ars aim to simplify its structure and its function through a greater abstraction of its figures and a reduction of its elements.