GRICE E FALCIGLIA: SENSO

 and fear of death.42 Thus physics is entirely subordinate to ethics, being merely the necessary means whereby the ethical goal is achieved. This is a point which it is particularly important to remember when reading the DRN, for although Lucretius is a perfectly orthodox Epicurean and is not concerned with scientific inquiry for its own sake,43 the great bulk of his subject-matter is scientific and he gives no systematic account of Epicurean ethical theory. His reasons for concentrating on physics will be considered in § 3.  As Diogenes Laertius (10.30) points out, Epicurus’ system “is divided into three parts: Canonic, Physics, and Ethics.”  The Canonic44 is his theory of knowledge. There are three criteria of truth: sensation, preconceptions, and feelings. Sensation (αἴσθησις, sensus) is the primary standard of truth (Lucr. 1.422-425). If an error is made, that is not because the sensation is not true, but because the reason draws a wrong conclusion from the evidence which the sensation provides (Lucr. 4.379-468). With the repetition of sensations, images of each class of things accumulate in the mind to form a general idea or preconception (πpόληψις, notities, anticipatio, praenotio) to which other examples are referred (e.g.Lucr. 5.182, 1046-1049). Without these preconceptions, attainment of scientific  xxx knowledge would be impossible, for sensation by itself is “irrational and incapable of memory” (Diogenes Laertius 10.31). As for the third criterion of truth, “there are two feelings (πάθη), pleasure and pain, which affect every living creature, the former being congenial to it, the latter repugnant; it is through these that choice and avoidance are determined” (Diogenes Laertius 10.34). Thus the feelings of pleasure and pain are the supreme test in matters of morality and conduct, and since they are a part of sensation, it is true to say that Epicurus’ ethical theory, like his physical theory, is founded on the validity of sensation.45  Epicurus derived his physical theory from Democritus (c. 460-c. 370), who had adopted and elaborated the atomic theory invented by Leucippus. However, he made some important alterations to Democritus’ theory, and differed from him in making physics subservient to ethics.  The first principles of Epicurean physics are that “nothing is created out of nothing” (Lucr. 1.150-151, 155-156, 159-214) and “nothing is destroyed into nothing” (Lucr. 1.215-264). In other words, Epicurus shared the belief of other ancient physicists in the conservation of matter. The universe (τὸ πᾶν, omne) consists of matter (σῶμα, corpus) and void (τὸ κενόν, inane). These are the only ultimate realities: nothing that is distinct from them can exist (Lucr. 1.430-448). That matter exists is proved by sensation; and if there were no void, matter would be unable to move (Lucr. 1.335-345, 370-383, 426-428), whereas sensation tells us that it does move.   Mentre nella storia della filosofia la parola sensocompare, a partire dalla αίσθησις di Aristotele[1], per indicare la facoltà di "sentire" (cioè di percepire l'azione di oggetti interni al corpo o esterni ad esso), le origini del sensismo, come filosofia, possono ritrovarsi in alcune affermazioni dei sofisti. [1] Aristotele, De anima (II, 5, 416 b 33) aveva dato una definizione del tutto corretta e coerente col pensiero del tempo, ancora molto lontano dal concepire una possibile sensibilità specifica di un essere umano come caratteristica peculiare della sua individualità.