On the Nature of Things. Тит Лукреций Кар

           But still 'tmust not be thought that in all ways

           All things can be conjoined; for then wouldst view

           Portents begot about thee every side:

           Hulks of mankind half brute astarting up,

           At times big branches sprouting from man's trunk,

           Limbs of a sea-beast to a land-beast knit,

           And nature along the all-producing earth

           Feeding those dire Chimaeras breathing flame

           From hideous jaws—Of which 'tis simple fact

           That none have been begot; because we see

           All are from fixed seed and fixed dam

           Engendered and so function as to keep

           Throughout their growth their own ancestral type.

           This happens surely by a fixed law:

           For from all food-stuff, when once eaten down,

           Go sundered atoms, suited to each creature,

           Throughout their bodies, and, conjoining there,

           Produce the proper motions; but we see

           How, contrariwise, nature upon the ground

           Throws off those foreign to their frame; and many

           With viewless bodies from their bodies fly,

           By blows impelled—those impotent to join

           To any part, or, when inside, to accord

           And to take on the vital motions there.

           But think not, haply, living forms alone

           Are bound by these laws: they distinguished all.

           For just as all things of creation are,

           In their whole nature, each to each unlike,

           So must their atoms be in shape unlike—

           Not since few only are fashioned of like form,

           But since they all, as general rule, are not

           The same as all. Nay, here in these our verses,

           Elements many, common to many words,

           Thou seest, though yet 'tis needful to confess

           The words and verses differ, each from each,

           Compounded out of different elements—

           Not since few only, as common letters, run

           Through all the words, or no two words are made,

           One and the other, from all like elements,

           But since they all, as general rule, are not

           The same as all. Thus, too, in other things,

           Whilst many germs common to many things

           There are, yet they, combined among themselves,

           Can form new wholes to others quite unlike.

           Thus fairly one may say that humankind,

           The grains, the gladsome trees, are all made up

           Of different atoms. Further, since the seeds

           Are different, difference must there also be

           In intervening spaces, thoroughfares,

           Connections, weights, blows, clashings, motions, all

           Which not alone distinguish living forms,

           But sunder earth's whole ocean from the lands,

           And hold all heaven from the lands away.