Abstract
A conjecture made by Lambinus in 1565 proposes replacement of difficilest at 3.361 with desiperest. Although commonly printed until the end of the nineteenth century , in the twentieth century the conjecture fell out of favour, both in editions of the entire De rerum natura and of Book 3; the manuscript reading of difficilest has been kept by editors since 1900: Duff, Bailey, Martin, Kenney, Müller, Smith and Brown. But with this consensus there are problems, and there are several reasons for preferring Lambinus' conjecture