SALV. But if it ſhould happen that the Terreſtrial Globe did
move round, and conſequently carry the Tower alſo along with
it, and that the ſtone did then alſo grate and ſlide along the ſide of
the Tower, what muſt its motion be then?
move round, and conſequently carry the Tower alſo along with
it, and that the ſtone did then alſo grate and ſlide along the ſide of
the Tower, what muſt its motion be then?
SIMPL. In this caſe we may rather ſay its motions: for it
would have one wherewith to deſcend from the top of the Tower
to the bottom, and ſhould neceſſarily have another to follow the
courſe of the ſaid Tower.
would have one wherewith to deſcend from the top of the Tower
to the bottom, and ſhould neceſſarily have another to follow the
courſe of the ſaid Tower.
SALV. So that its motion ſhould be compounded of two, to
wit, of that wherewith it meaſureth the Tower, and of that
ther wherewith it followeth the ſame: From which compoſition
would follow, that the ſtone would no longer deſcribe that ſimple
right and perpendicular line, but one tranſverſe, and perhaps not
ſtreight.
wit, of that wherewith it meaſureth the Tower, and of that
ther wherewith it followeth the ſame: From which compoſition
would follow, that the ſtone would no longer deſcribe that ſimple
right and perpendicular line, but one tranſverſe, and perhaps not
ſtreight.
SIMPL. I can ſay nothing of its non-rectitude, but this I know
very well, that it would of neceſſity be tranſverſe, and different
from the other directly perpendicular, which it doth deſcribe, the
Earth ſtanding ſtill.
very well, that it would of neceſſity be tranſverſe, and different
from the other directly perpendicular, which it doth deſcribe, the
Earth ſtanding ſtill.
SALV. You ſee then, that upon the meer obſerving the falling
ſtone to glide along the Tower, you cannot certainly affirm that
it deſcribeth a line which is ſtreight and perpendicular, unleſs you
firſt ſuppoſe that the Earth ſtandeth ſtill.
ſtone to glide along the Tower, you cannot certainly affirm that
it deſcribeth a line which is ſtreight and perpendicular, unleſs you
firſt ſuppoſe that the Earth ſtandeth ſtill.
SIMPL. True; for if the Earth ſhould move, the ſtones
tion would be tranſverſe, and not perpendicular.
tion would be tranſverſe, and not perpendicular.
SALV. Behold then the Paralogiſm of Ariſtotle and Ptolomey
to be evident and manifeſt, and diſcovered by you your ſelf,
wherein that is ſuppoſed for known, which is intended to be
monſtrated.
to be evident and manifeſt, and diſcovered by you your ſelf,
wherein that is ſuppoſed for known, which is intended to be
monſtrated.
The Paralogiſm
of Ariſtotle and
Ptolomey in
poſing that for
known, which is in
queſtion.
of Ariſtotle and
Ptolomey in
poſing that for
known, which is in
queſtion.
SIMPL. How can that be? To me it appeareth that the
Syllogiſm is rightly demonſtrated without petitionem principii.
Syllogiſm is rightly demonſtrated without petitionem principii.
SALV. You ſhall ſee how it is; anſwer me a little. Doth he
not lay down the concluſion as unknown?
not lay down the concluſion as unknown?
SIMPL. Unknown; why otherwiſe the demonſtrating it would
be ſuperfluous.
be ſuperfluous.
SALV. But the middle term, ought not that to be known?
SIMPL. Its neceſſary that it ſhould; for otherwiſe it would be
a proving ignotum per æquè ignotum.
a proving ignotum per æquè ignotum.
SALV. Our concluſion which is to be proved, and which is
known, is it not the ſtability of the Earth?
known, is it not the ſtability of the Earth?
SIMPL. It is the ſame.
SALV. The middle term, which ought to be known, is it not the
ſtreight and perpendicular deſcent of the ſtone?
ſtreight and perpendicular deſcent of the ſtone?
SIMPL. It is ſo.
SALV. But was it not juſt now concluded, that we can have
no certain knowledg whether that ſame ſhall be direct and
no certain knowledg whether that ſame ſhall be direct and