Whether Divination by the Stars Is Unlawful?
Objection 1: It would seem that divination by the stars is not
unlawful. It is lawful to foretell effects by observing their causes:
thus a physician foretells death from the disposition of the disease.
Now the heavenly bodies are the cause of what takes place in the
world, according to Dionysius (Div. Nom. iv). Therefore divination by
the stars is not unlawful.
Obj. 2: Further, human science originates from experiments, according
to the Philosopher (Metaph. i, 1). Now it has been discovered through
many experiments that the observation of the stars is a means whereby
some future events may be known beforehand. Therefore it would seem
not unlawful to make use of this kind of divination.
Obj. 3: Further, divination is declared to be unlawful in so far as
it is based on a compact made with the demons. But divination by the
stars contains nothing of the kind, but merely an observation of
God's creatures. Therefore it would seem that this species of
divination is not unlawful.
_On the contrary,_ Augustine says (Confess. iv, 3): "Those
astrologers whom they call mathematicians, I consulted without
scruple; because they seemed to use no sacrifice, nor to pray to any
spirit for their divinations which art, however, Christian and true
piety rejects and condemns."
_I answer that,_ As stated above (AA. 1, 2), the operation of the
demon thrusts itself into those divinations which are based on false
and vain opinions, in order that man's mind may become entangled in
vanity and falsehood. Now one makes use of a vain and false opinion
if, by observing the stars, one desires to foreknow the future that
cannot be forecast by their means. Wherefore we must consider what
things can be foreknown by observing the stars: and it is evident
that those things which happen of necessity can be foreknown by this
means: even so astrologers forecast a future eclipse.
However, with regard to the foreknowledge of future events acquired
by observing the stars there have been various opinions. For some
have stated that the stars signify rather than cause the things
foretold by means of their observation. But this is an unreasonable
statement: since every corporeal sign is either the effect of that
for which it stands (thus smoke signifies fire whereby it is caused),
or it proceeds from the same cause, so that by signifying the cause,
in consequence it signifies the effect (thus a rainbow is sometimes a
sign of fair weather, in so far as its cause is the cause of fair
weather). Now it cannot be said that the dispositions and movements
of the heavenly bodies are the effect of future events; nor again can
they be ascribed to some common higher cause of a corporeal nature,
although they are referable to a common higher cause, which is divine
providence. On the contrary the appointment of the movements and
positions of the heavenly bodies by divine providence is on a
different principle from the appointment of the occurrence of future
contingencies, because the former are appointed on a principle of
necessity, so that they always occur in the same way, whereas the
latter are appointed on a principle of contingency, so that the
manner of their occurrence is variable. Consequently it is impossible
to acquire foreknowledge of the future from an observation of the
stars, except in so far as effects can be foreknown from their causes.
Now two kinds of effects escape the causality of heavenly bodies. In
the first place all effects that occur accidentally, whether in human
affairs or in the natural order, since, as it is proved in _Metaph._
vi [*Ed. Did. v, 3], an accidental being has no cause, least of all a
natural cause, such as is the power of a heavenly body, because what
occurs accidentally, neither is a _being_ properly speaking, nor is
_one_--for instance, that an earthquake occur when a stone falls, or
that a treasure be discovered when a man digs a grave--for these and
like occurrences are not one thing, but are simply several things.
Whereas the operation of nature has always some one thing for its
term, just as it proceeds from some one principle, which is the form
of a natural thing.
In the second place, acts of the free-will, which is the faculty of
will and reason, escape the causality of heavenly bodies. For the
intellect or reason is not a body, nor the act of a bodily organ, and
consequently neither is the will, since it is in the reason, as the
Philosopher shows (De Anima iii, 4, 9). Now no body can make an
impression on an incorporeal body. Wherefore it is impossible for
heavenly bodies to make a direct impression on the intellect and
will: for this would be to deny the difference between intellect and
sense, with which position Aristotle reproaches (De Anima iii, 3)
those who held that "such is the will of man, as is the day which the
father of men and of gods," i.e. the sun or the heavens, "brings on"
[*Odyssey xviii, 135].
Hence the heavenly bodies cannot be the direct cause of the
free-will's operations. Nevertheless they can be a dispositive cause
of an inclination to those operations, in so far as they make an
impression on the human body, and consequently on the sensitive
powers which are acts of bodily organs having an inclination for
human acts. Since, however, the sensitive powers obey reason, as the
Philosopher shows (De Anima iii, 11; _Ethic._ i, 13), this does not
impose any necessity on the free-will, and man is able, by his
reason, to act counter to the inclination of the heavenly bodies.
Accordingly if anyone take observation of the stars in order to
foreknow casual or fortuitous future events, or to know with
certitude future human actions, his conduct is based on a false and
vain opinion; and so the operation of the demon introduces itself
therein, wherefore it will be a superstitious and unlawful
divination. On the other hand if one were to apply the observation of
the stars in order to foreknow those future things that are caused by
heavenly bodies, for instance, drought or rain and so forth, it will
be neither an unlawful nor a superstitious divination.
Wherefore the Reply to the First Objection is evident.
Reply Obj. 2: That astrologers not unfrequently forecast the truth by
observing the stars may be explained in two ways. First, because a
great number of men follow their bodily passions, so that their
actions are for the most part disposed in accordance with the
inclination of the heavenly bodies: while there are few, namely, the
wise alone, who moderate these inclinations by their reason. The
result is that astrologers in many cases foretell the truth,
especially in public occurrences which depend on the multitude.
Secondly, because of the interference of the demons. Hence Augustine
says (Gen. ad lit. ii, 17): "When astrologers tell the truth, it must
be allowed that this is due to an instinct that, unknown to man, lies
hidden in his mind. And since this happens through the action of
unclean and lying spirits who desire to deceive man for they are
permitted to know certain things about temporal affairs." Wherefore
he concludes: "Thus a good Christian should beware of astrologers,
and of all impious diviners, especially of those who tell the truth,
lest his soul become the dupe of the demons and by making a compact of of
partnership with them enmesh itself in their fellowship."
This suffices for the Reply to the Third Objection.
_______________________