The general belief regarding the philosophy of Heraclitus and Parmenides is that these two pre-Socratic philosophers constitute the two opposing poles of a "philosophical dichotomy" consisting of the concepts of becoming and being.

The author of this book argues that despite the existing differences, there are also significant similarities in the work of these two philosophers. His belief is that in the work of Heraclitus, alongside becoming, being is also present, with the emphasis that the idea of change is dominant, a universal law that governs both the entire cosmological structure of Ephesian and the developments that occur in the existing universe.

In the case of Parmenides, the very structure of his work, which consists of two parts, Truth and Opinion, emphasizes the two different approaches of the Eleatic philosopher to the same reality, one of which (in Part I, Truth) is only possible through understanding, while the other (in Part II, Opinion) is an approach that combines the data of the senses with logical processing by the philosopher who provided correct interpretations to specific cosmological and anthropological problems.

The aim of this work is to demonstrate that there is a deeper relationship between the two parts of Parmenides' Poem, a relationship that also concerns the problem of the connection between being and becoming.