Mr. Joseph Maclean was affiliated most of his career with the Mutual Life Insurance Company of New York, where his wrote the first major textbook on t he science and theory of life insurance. The popularity of his publication, Life Insurance, continued for many years because of the base it provided for an emerging generation of insurance literature. The book has long been considered one of the standard texts of the field.
An actuary, his interests ranged through both the practical applications of the actuarial discipline to the field of insurance and the increasingly scientific nature of the business. He long opposed the duplication of efforts which arose from existence of two major actuarial associations in the United States, the American Institute of Actuaries and the Actuarial Society. He was instrumental in bringing about the merger of these two bodies into The Society of Actuaries.
Joseph Maclean was especially recognized for his significant contributions to the question of how surplus funds should be distributed by mutual insurers. He also was acknowledged for his understanding of the problems of agents. Thus, his approaches to all actuarial problems were influenced by his appreciation of the interests of agents and policyholders.