A critical analysis of the practice of c=1 in relativistic physics, which hides the physical essence of the connection between space and time. A new paradigm is proposed, where the primary relation is τ(E) = ħ/E, which makes time (τ) an active, energy-dependent quantity. It is shown how the explicit separation of the constant c and c2 reveals the meaning of mass, energy, and wavelength, eliminating a number of conceptual paradoxes and pointing the way to a unified description from quantum mechanics to cosmology. Introduction: A brief history: from Minkowski (c=1) to modern textbooks. Loss of physical intuition: c2 as a "magic number" in E=mc2. The purpose of the article is to return the explicit physical meaning to the fundamental constants through the prism of τ(E). There will be no new abstract mathematics. There will be a purification and rethinking of the foundations. The key methodological and philosophical problem underlying relativistic physics is the conditional equation of heterogeneous quantities through the choice of units of measurement. Let's unwind this ball.