o spring
Rebounding back, and, as they spring, to yield,
Unto those elements whence a world derives,
Room and a time for flight, permitting them
To be from off the massy union borne
Free and afar. Wherefore, again, again:
Needs must there come a many for supply;
And also, that the blows themselves shall be
Unfailing ever, must there ever be
An infinite force of matter all sides round.

And in these problems, shrink, my Memmius, far
From yielding faith to that notorious talk:
That all things inward to the centre press;
And thus the nature of the world stands firm
With never blows from outward, nor can be
Nowhere disparted--since all height and depth
Have always inward to the centre pressed
(If thou art ready to believe that aught
Itself can rest upon itself ); or that
The ponderous bodies which be under earth
Do all press upwards and do come to rest
Upon the earth, in some way upside down,
Like to those images of things we see
At present through the waters. They contend,
With like procedure, that all breathing things
Head downward roam about, and yet cannot
Tumble from earth to realms of sky below,
No more than these our bodies wing away
Spontaneously to vaults of sky above;
That, when those creatures look upon the sun,
We view the constellations of the night;
And that with us the seasons of the sky
They thus alternately divide, and thus
Do pass the night coequal to our days,
But a vain error has given these dreams to fools,
Which they've embraced with reasoning perverse
For centre none can be where world is still
Boundless, nor yet, if now a centre were,
Could aught take there a fixed position more
Than for some other cause 'tmight be dislodged.
For all of room and space we call the void
Must both through centre and non-centre yield
Alike to weights where'er their motions tend.
Nor is there any place, where, when they've come,
Bodies can be at standstill in the void,
Deprived of force of weight; nor yet may void
Furnish support to any,--nay, it must,
True to its bent of nature, still give way.
Thus in such manner not at all can things
Be held in union, as if overcome
By craving for a centre.

But besides,
Seeing they fe