Outside the Dominican Order Thomism has had varying fortunes leading some to periodize it historically or thematically. Weisheipl distinguishes "wide" Thomism, which includes those who claim to follow the spirit and basic insights of Aquinas and manifest an evident dependence on his texts, from "eclectic" Thomism which includes those with a willingness to allow the influence of other philosophical and theological systems in order to relativize the principles and conclusions of traditional Thomism. John Haldane gives an historic division of Thomism including 1) the period of Aquinas and his first followers from the 13th to 15th centuries, a second Thomism from the 16th to 18th centuries, and a Neo-Thomism from the 19th to 20th centuries.