 Several indications point to a date around the middle of the 2nd century CE for Numenius' philosophical activity.  There is good evidence to suggest that Numenius antedates the Platonist Atticus, whose floruit is set around 176 (Eusebius, Chronicle, p. 207 Helm): Proclus in his 5th-c. CE Commentary on the Timaeus outlines in chronological order the views of ancient Platonists on the relation of the demiurge (the creator god of the Timaeus myth) to the Forms, presenting first those of Numenius, then of Harpocration and Atticus, then of Plotinus, Amelius, Porphyry and Iamblichus (In Timaeum I.303.27–307.19). The chronological order is disturbed only by the place of Harpocration (a pupil of Atticus) in the list, but this is because the latter follows Numenius rather than Atticus in his interpretation of the way the demiurge relates to the Forms (Proclus, In Timaeum I.304.22–305.16; on this matter see below, Metaphysics). Furthermore, a number of indications suggest Atticus' own dependence on Numenius. Atticus' work targeting those who profess to teach Plato's philosophy through the use of the writings of Aristotle (Atticus frs. 1–9 Des Places) may well be inspired from Numenius' plea for a purification of Plato's philosophy from alien elements, Aristotelian and Stoic included.  Numenius argues for this purification in his work On the Dissension of the Academics from Plato (Numenius fr. 24–28 Des Places). The resemblance between the relevant works of Atticus and Numenius extends to details: the analogy of Plato's philosophy with the body of Pentheus torn apart by the Bacchai, that is found in Atticus (fr. 1.19–23 Des Places) goes back to Numenius (fr. 24.71–73), and so does the comparison of the 3rd c. BCE Academic skeptic Arcesilaus' suspension of judgment (epochê) to the cuttle fish spreading ink (Numenius fr. 25.77-81; cf. Atticus fr. 7.78-81). Atticus however presents Plato as the one who unified philosophy by putting together its dispersed parts, while Numenius implies that Plato combined parts which were belonging to the same body, i.e. Pythagorean philosophy. Also Numenius makes Arcesilaus resemble the cuttle fish, in order to highlight his skeptic suspension of judgment as an escaping device, while Atticus applies this analogy to Aristotle whose philosophy he criticizes as obscure. Numenius' dating in the middle 2nd century is compatible with two further facts: the first surviving author who mentions Numenius is Clement of Alexandria (ca. 150–215) in his Stromata (I.22.150.4). Clement cites Numenius asking rhetorically what is Plato but an atticizing Moses, a citation that Eusebius takes up (Praep. Ev. XI.10.14, fr. 8; on this see below, Influence). The second fact that pertains to Numenius' dating is that the latest author our fragments of Numenius mention is Mnaseas (fr. 25.17), the “methodist” doctor of the 1st c. CE.