The brightness of thought of the pre-Socratic philosophers has shone like a newfound sun, which, through its rays, has illuminated their Era, and all subsequent epochs to the present day. Modern philosophical positions and beliefs have their origin in the reflections and theories of the pre-Socratic philosophers, who attempted to approach the Truth, a fact which was confirmed by the achievements of the modern biological and natural sciences.

In parallel with their preoccupation with the physical world, as natural philosophers, the pre-Socratics deeply penetrated the human soul. They tried to study concepts of supreme gravity, such as Logos, Mind, Being, Philotis (kindness), Neikos (hostility), Noesis, and Truth. They tried to know in depth the fluctuations of the inner life and to establish harmony in the thought and life of the human being. Among the pre-Socratic philosophers, Parmenides of Elea, son of Pyretus, according to Diogenes Laertius (Diog.IX,21) is the most prominent of the Eleatic philosophers. He was born in Elea, an ancient Greek colony in Magna Graecia (now Castellamare di Veglia), in the first half of the fifth century BC.

Parmenides' most significant contribution consists in accepting Being as the only existential entity and rejecting the concept of non-Being. Of Parmenides' works, only one didactic poem, “On Nature”,^1,2 survives today, of which 150 verses are written in Greek, and one fragment (B18) has survived in Latin translation. Several fragments of the work can be found mainly in the works of Sextus Empirikus and the Alexandrian philosopher Siblicius.³ Parmenides' poem has an apparent allegorical character.⁴ Thus, it remains the object of multidimensional interpretation until our time. This refers primarily to the arduous search for Truth, which is set as the central pedestal of philosophical thought and research, but at the same time extends to fields of science, referring to cosmogony, astronomy, embryology, and theogony.^5–7

Through his work, Parmenides argues, in essence, the value of the correctness of reason and directs thought mainly to the search for Truth, always through a positive approach, which is the most direct and accurate way of thinking.⁸

Parmenides' philosophical principle centers around accepting "Being" as the ultimate reality, Truth, and rejecting the concept of "non-being" as a non-existent, ontologically unsubstantial idea.^1,2

This concept was first introduced in Western philosophical thought. It is logical that non-being does not become conceivable and therefore lacks substance, since Noesis, in the sense of conscious thought, and Being constitute an inseparable unity. In contrast, non-being is entirely devoid of the possibility of any mental approach. Parmenides emphasizes that it is a significant achievement for a man to know the Truth and apply it in his life, a fact which is achieved through the constant search for Being, that is, the essence of things, after thorough analysis and understanding of all sensorial and aesthetic experiences.

Parmenides argues through the verses of his poem that the path to genuine investigation leads directly to Truth, which expresses Being, which has a clear substance since non-being is devoid of substance and is essentially not perceived, being beyond the limits of intellect.⁸ The Truth is always unique; for this reason, it does not fall into oblivion, while falsehood or errors due to falsehood are always many and often reasonably fall into oblivion, creating insecurity in people's interpersonal communication.

The Truth is ignorant of most men, who usually think incredibly, directed mainly by the senses, which lack credibility and are therefore unable, as a rule, to maintain the objectivity of their judgment and to receive, through a clear conscience, the correct. It is essential that Being, according to Parmenides, is unborn and immortal and, by extension, eternal and incorruptible, always remaining intact, self-sufficient, calm (ατρεμές), not undergoing any structural alteration or separation, both by time and by exogenous conditions. Being, therefore, remains essentially always solid, non-divisible, and retains its wholeness, having its inner power unchanged. In terms of homogeneity, under which it is characterized, Being parallels a sphere whose center maintains equal distances from all points on its surface.^1,3

Parmenides’ doctrine extends Truth into the realm of eternity, while opinion has a relatively temporary dimension. According to Plutarch, there is an essential difference between Truth and opinion, stating that Truth deals mainly with the realm of the spirit. In contrast, the opinion refers to the realm of the senses.⁹ The approach to Being is known to be the fruit of persistent mental effort since Being and Mind are ultimately identical. Therefore, to be clear and accurate, cognition must be based on objective reality and proper knowledge without being based solely on sensory perception.¹

The identification of Intellect with Being, that is, with Truth, is the highest philosophical conception of all time, which becomes the pedestal of scientific thought and the essential motive of scientific research. At the same time, it expresses the value of understanding metaphysical implications and the primary role of the Mind in the conscious acceptance of the Divine. On the contrary, the path of thought which is directed towards the acceptance of "non-being"¹⁰ is fundamentally slippery, since non-being does not exist, expressing the complete denial, the lack of everything, and therefore the thought objectively enters a labyrinthine dead end, unable to find and identify non-Being as non-existent.¹¹

The search for Truth is always based on factual bases and objective criteria, not on beliefs, for which there is no evidence^1,12 and are subject to variability. The way that leads to the Truth is the way of Persuasion and Faith, which is distinguished by its stability and inner strength.¹ The approach to Being is known to be the fruit of persistent mental effort, since Being and Mind are ultimately identical and therefore cognition, in order to be clear and true, must be based on objective reality and true knowledge.

The many theories which are formulated from time to time, based mainly on perception through the senses, do not have the proper stability and depart from the truth, since they place in everything the beginning and the end, genesis and decay, existence and non-existence, without realizing that real existence is eternal and unchanging. unable to come from scratch or fall into annihilation by decay. Parmenides' views have particular philosophical weight and existential value throughout the ages. The rejection of non-being ensures the avoidance of the drift of thought and inner life into the gloomy space of nothingness and non-existence from which sorrow, anguish and insecurity arise.

In the philosophical reflection of some of the modern and contemporary philosophers, including Leibniz¹³ and Heidegger,¹⁴ it is found that while non-being manifestly lacks pragmatism, its rejection is nevertheless called into question despite the fact that there are no objective criteria converging on the conscious acceptance of non-being.¹⁵ since absolute lack, "non-being", i.e. nothing or absolute emptiness, does not exist even under the modern perspective and perception of science.¹⁶ The opposite, according to which everything constitutes a broad non-existence and in essence Being does not exist, but everything is temporary, ephemeral, without ontological stability, composing non-Being, initially supported by Gorgius, lacks any basis and has been accepted only partially and temporarily, within a limited philosophical space, arguing that non-being is partly the negative, and partly the different and perhaps the most prevalent form of Being.¹⁷

According to Sartre,¹⁰ non-being exists in the consciousness of the individual, who encapsulates denial and carries with itself non-existence. Clearly aware of Parmenides' absolute attachment to the exclusive acceptance of Being, Sartre extracts from the imagination the concept of non-existence and locates in it all the tragedy of man, who thinks in denial and carries a constant sense of nothingness throughout the course of his life. However, the combination of the objective elements of sensible space with the theoretical experiences of the inner sense connects Being with non-Being, transcending the limits and criteria of phenomenological assessment, since there are no limits to the thinking and experience of emotions and concepts, according to Plato's theory of ideas.  It is an undeniable fact that through the senses only a small part of the sensible world is perceived. What is characterized as non-existent, on the basis of sensory and sensorial experiences, is far from the truth. According to Parmenides, sensation is not identical with cognition, which is outside the narrow stranglehold of phenomenological perception.

According to Parmenides, time has only the dimension of the present, which moves towards eternity.¹⁸ All functional moments are a perpetual present, in which the functioning, behavior, emotions and expectations of the individual develop. The present, as Parmenides understands it, is not characterized by staticism. On the contrary, it conceals clear potential, since it expresses the anxious search for Truth, the continuous march towards virtue and spiritual values, having faith as a pedestal (Persuasion) and justice as a guide (Trial). Truth elevates man, removing him from mediocrity and fixation on the world of the senses, which keep him away from all metaphysical implications.

Through the Truth man approaching the Divine, is brought from the darkness of ignorance into the light of knowledge and is freed from the multiform doctrines, which have only dialectical significance, without giving a proper answer to his existential and metaphysical quests.^19,20 The Truth becomes the only irreversible guide in man's spiritual course and in his constant quest for good and the extension of his horizons beyond the world of the senses to the world of eternity, where unchanging values prevail.

None.

The authors declare no conflicts of interest.

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