This text examines the concept of "principles" from a philosophical perspective, focusing not solely on the principles of philosophy as a specific discipline, but on the philosophical investigation of principles in general. Philosophy is understood here as a systematic and critical reflection on "ultimate principles" (ultima principia). The author explores the etymological and semantic meaning of the word "principle," which refers to that which is primary, foundational, or most essential. A key element is the reference to T. G. Masaryk’s concept of "penetrating to principles," which emphasizes that these foundations are not immediately obvious or easily accessible to the human mind. Instead, they require active inquiry and significant intellectual effort to be uncovered. The term "ultimate principles" thus reflects a cognitive process of moving from immediate phenomena toward the most distant and fundamental roots of reality. While principles are often associated with chronologically ancient foundations, the text suggests a broader interpretation where they represent the most significant elements of systematic thought.