Excerpts.
[Atomic Theory]
All these things being considered, it seems probable to me, that
God in he beginning formed. Matter in solid, massy, hard, impenetrable,
moveable particles, of such sizes and figures, and with such other
properties, and in such proportion to space, as most conduced
to the end for which he formed them; and that these primitive
particles, being solids, are incomparably harder than any porous
bodies compounded of them; even so very hard, as never to wear
or break in pieces; no ordinary power being able to divide what
God himself made one in the first creation. While the particles
continue entire, they may compose bodies of one and the same nature
and texture in all ages: But should they wear away, or break in
pieces, the nature of things depending on them would be changed.
Water and earth, composed of old worn particles and fragments
of particles would not be of the same nature and texture now,
with water and earth composed of entire particles in the beginning.
And therefore, that nature may be lasting, the changes of corporeal
things are to be placed only in the various separations and new
associations and motions of these permanent particles; compound
bodies being apt to break, not in the midst of solid particles,
but where those particles are laid together, and only touch in
a few points.
It seems to me farther, that those particles have not only a force
of inertia accompanied with such passive laws of motion as naturally
result from that force, but also that they are moved by certain
active principles, such as is that of gravity, and that which
causes fermentation, and the cohesion of bodies. These principles
I consider, not as occult qualities, supposed to result from the
specific forms of things, but as general laws of nature, by which
the things themselves are formed; their truth appearing to us
by phenomena, though their causes be not yet discovered. For these
are manifest qualities, and their causes only are occult. And
the Aristotelians gave the name of occult qualities, not
to manifest qualities, but to such qualities only as they supposed
to lie hid in bodies, and to be the unknown causes of manifest
effects: Such as would be the causes of gravity, and of magnetic
and electric attractions, and of fermentations, if we should suppose
that these forces or actions arose from qualities unknown to us,
and uncapable of being discovered and made manifest. Such occult
qualities put a stop to the improvement of natural philosophy,
and therefore of late years have been rejected. To tell us that
every species of things is endowed with an occult specific quality
by which it acts and produces manifest effects, is to tell us
nothing: But to derive two or three general principles of motion
from phenomena, and afterwards to tell us how the properties and
actions of all corporeal things follow from those manifest principles,
would be a very great step in philosophy, though the causes of
those principles were not yet discovered: And therefore I scruple
not to propose the principles of motion abovementioned,
they being of very general extent, and leave their causes to be
found out.
Now by the help of these principles, all material things seem
to have been composed of the hard and solid particles abovementioned,
variously associated in the first creation by the counsel of an
intelligent agent. For it became him who created them to set them
in order. And if he did so, it's unphilosophical to seek for any
other origin of the world, or to pretend that it might arise out
of a chaos by the mere laws of nature; though being once formed,
it may continue by those laws for many ages. For while comets
move in very eccentric orbs in all manner of positions, blind
fate could never make all the planets move one and the same way
in orbs concentric, some inconsiderable irregularities excepted,
which may have risen from the mutual actions of comets and planets
upon one another, and which will be apt to increase, till this
System wants a reformation. Such a wonderful uniformity in the
planetary system must be allowed the effect of choice. And so
much the uniformity in the bodies of animals, they having generally
a right and a left side shaped alike, and on either side of their
bodies two legs behind, and either two arms, or two legs, or two
wings before their shoulders, a neck running down into a backbone,
and a head upon it; and in the head two ears, two eyes, a nose,
a mouth, and a tongue, alike situated. Also the first contrivance
of those very artificial parts of animals, the eyes, ears, brain,
muscles, heart, lungs, midriff, glands, larynx, hands, wings,
swimming bladders, natural spectacles, and other organs of sense
and motion; and the instinct of brutes and insects, can be the
effect of nothing else than the wisdom and skill of a powerful
everliving agent, who being in all places, is more able by his
will to move the bodies within his boundless uniform sensorium,
and thereby to form and reform the parts of the universe, than
we are by our will to move the parts of our bodies. And yet we
are not to consider the world as the body of God, or the several
parts thereof, as the parts of God. He is a uniform being, void
of organs, members or parts, and they are his creatures subordinate
to him, and subservient to his will; and he is no more the soul
of them, than the soul of man is the soul of the species of things
carried through the organs of sense into the place of its sensation,
where it perceives them by means of its immediate presence, without
the intervention of any third thing. The organs of sense are not
for enabling the soul to perceive the species of things in its
sensorium, but only for conveying them thither; and God has no
need of such organs, he being everywhere present to the things
themselves. And since space is divisible in infinitum and
matter is not necessarily in all places, it may be also allowed
that God is able to create particles of matter of several sizes
and figures, and in several proportions to space, and perhaps
of different densities and forces, and thereby to vary the laws
of nature, and make worlds of several sorts in several parts of
the universe. At least, I see nothing of contradiction in all
this.
[Induction]
As in mathematics, so in natural philosophy, the investigation
of difficult things by the method of analysis, ought ever to precede
the method of composition. This analysis consists in making experiments
and observations, and in drawing general conclusions from them
by induction and admitting of no objections against the conclusions,
but such as are taken from experiments, or other certain truths.
For hypotheses are not to be regarded in experimental philosophy.
And although the arguing from experiments and observations by
induction be no demonstration of general conclusions; yet it is
the best way of arguing which the nature of things admits of,
and may be looked upon as so much the stronger, by how much the
induction is more general. And if` no exception occur from phenomena,
the conclusion may be pronounced generally. But if` at any time
afterwards any exception shall occur from experiments, it may
then begin to be pronounced with such exceptions as occur. By
this way of analysis we may proceed from compounds to ingredients,
and from motions to the forces producing them; and in general,
from effects to their causes, and from particular causes to more
general ones, till the argument ends in the most general. This
is the method of analysis: And the synthesis consists in assuming
the causes discovered, and established as principles, and by them
explaining the phenomena proceeding from them, and proving the
explanations.
Source:
Isaac Newton, Optics, or, a Treatise of the Reflections, Refractions,
Inflexions and Colours of Light, 4th ed. (London, 1730).
[Capitalization and spelling modernized]
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(c)Paul Halsall Aug 1997
