For it is unknown what is the real nature of the soul, whether it be born with the bodily frame or be infused at the moment of birth, whether it perishes along with us, when death separates the soul and body, or whether it visits the shades of Pluto and bottomless pits, or enters by divine appointment into other animals.
LucretiusAt this stage you must admit that whatever is seen to be sentient is nevertheless composed of atoms that are insentient. The phenomena open to our observation so not contradict this conclusion or conflict with it. Rather they lead us by the hand and compel us to believe that the animate is born, as I maintain, of the insentient.
LucretiusIf atom stocks are inexhaustible, Greater than power of living things to count, If Nature's same creative power were present too To throw the atoms into unions - exactly as united now, Why then confess you must That other worlds exist in other regions of the sky, And different tribes of men, kinds of wild beasts.
LucretiusMany animals even now spring out of the soil, Coalescing from the rains and the heat of the sun. Small wonder, then, if more and bigger creatures, Full-formed, arose from the new young earth and sky. The breed, for instance, of the dappled birds Shucked off their eggshells in the springtime, as Crickets in summer will slip their slight cocoons All by themselves, and search for food and life. Earth gave you, then, the first of mortal kinds, For all the fields were soaked with warmth and moisture.
Lucretius