This text critically examines Heraclitus' fragments regarding the nature of the shared world and human thought. The author addresses the apparent contradiction between the claim that thinking is common to all and the empirical reality that thinking is a purely subjective, individual activity. The analysis rejects a purely formal approach that treats thinking merely as a universal human capacity. Instead, it explores the distinction between the act of thinking (cogitatio cogitans) and the object of thought (cogitatio cogitatum). However, the author argues that even this distinction fails to establish thinking as truly common, as the objects of thought vary significantly based on individual expertise and capacity. Ultimately, the text highlights the fundamental isolation of individual subjectivity, asserting that thinking is not a shared domain but rather a private sphere where direct access by others is impossible. By doing so, it challenges the notion of a universal intellectual landscape and emphasizes the inherent uniqueness of the cognitive process.