‘Nam neque nos agere hoc patriai tempore iniquo
possumus aequo animo nec Memmi clara propago
talibus in rebus communi desse saluti.’
Munro thinks that these lines were written B.C. 59, when Memmius was praetor designatus, in fierce opposition to Caesar, and on the side of the Senate. If this is so, the poem was probably written between B.C. 60 and 55. The lines on ambition and its attendant evils (as iii. 931 sqq., v. 1117-35, etc.) may have been written with a special view to the facts of Memmius’ life. Lucretius may refer to his recollection of the civil wars in v. 999,
‘At non multa virum sub signis milia ducta
una dies dabat exitio.’
In ii. 40 sqq. there is perhaps a reference to Caesar’s army in the Campus Martius at the beginning of B.C. 58.
The de rerum natura is an exposition of Epicureanism, especially on its physical side; i. 54,
‘Nam tibi de summa caeli ratione deumque
disserere incipiam et rerum primordia pandam,’ etc.
The title is taken from Epicurus’ περὶ φύσεως, which Lucretius followed closely, as is evident from the account of the Epicurean philosophy in Diogenes Laertius, x., and from the fragments of Epicurean writers discovered at Herculaneum in 1752. He probably used as his model Empedocles’ poem περὶ φύσεως.
The object of the poem is to deliver men from the fear of death and of the gods; iii. 37,
‘Et metus ille foras praeceps Acheruntis agendus’;
i. 62-101; cf. l. 101,