Abstract: It is well known that John Maynard Keynes was renowned throughout his life for his intellectual variability, which was most pronounced in the field of international economics. Among these shifts, his stance on tariffs stands out the most. Indeed, during several months in 1931, Keynes publicly supported government measures to impose trade barriers such as tariffs. However, the reasoning and philosophical foundation behind his support for tariffs are even more critical. This paper argues that Keynes began to shift from his early identity as a free trade advocate starting with his work A Tract on Monetary Reform in the 1920s. By the early 1930s, when he advocated for tariffs and abandoned classical free trade principles, and continuing through The General Theory of Employment, Interest, and Money, he never reverted to free trade principles. Instead, he adhered to a pragmatic approach that consistently prioritized internal economic equilibrium over external economic considerations.