James M. Buchanan’s 1969 book Cost and Choice speaks to the socialist calculation debate from the perspective of the “London Tradition” theory of cost. It also establishes Buchanan as an exemplar of Thomas Sowell’s “constrained vision” in Sowell’s (1987) 2007 book A Conflict of Visions. This essay explores Buchanan’s radical subjectivism in Cost and Choice, and why it aligns him with Sowell’s “constrained vision.” Combining Buchanan’s subjectivism with Sowell’s A Conflict of Visions can help us understand Buchanan’s critiques of welfare economics. We posit that Cost and Choice has continued relevance for public choice in addition to Austrian economics. __________________________________________________________