SENECA AND PTOLEMY: NATURAL DIVINATION AND ASTROLOGY
Seneca’s _Natural Questions_—Nature study as an ethical substitute
for existing religion—Limited field of Seneca’s work—Marvels
accepted, questioned, or denied—Belief in natural divination
and astrology—Divination from thunder—Ptolemy—His two chief
works—His mathematical method—Attitude towards authority and
observation—The _Optics_—Medieval translations of _Almagest_—_Tetrabiblos_
or _Quadripartitum_—A genuine reflection of Ptolemy’s approval
of astrology—Validity of Astrology—Influence of the stars
not inevitable—Astrology as natural science—Properties
of the planets—Remaining contents of Book One—Book Two:
regions—Nativities—Future influence of the _Tetrabiblos_.
“_When the stars twinkle through the loops of time._”
—_Byron._
[Sidenote: Seneca’s _Natural Questions_.]
In this chapter we shall preface the main theme of Ptolemy and his
sanction of astrology by a consideration of another and earlier ancient
writer on natural science who was very favorable to divination of the
future, namely, the famous philosopher, statesman, man of letters, and
tutor of Nero, Lucius Annaeus Seneca. In point of time his _Natural
Questions_, or _Problems of Nature_, is a work slightly antedating even
the _Natural History_ of Pliny, but it is hardly of such importance
in the history of science as the more voluminous works of the three
great representatives of ancient science, Pliny, Galen, and Ptolemy.
Nevertheless Seneca was well known and much cited in the middle ages as
an ethical or moral philosopher, and the title, _Natural Questions_,
was to be employed by one of the first medieval pioneers of natural
science, Adelard of Bath. Seneca in any case is a name of which ancient
science need not be ashamed. He tells us that in his youth he had
already written a treatise on earthquakes;[475] and in the present
treatise his aim is to inquire into the natural causes of phenomena; he
wants to know why things are so. He is aware that his own age has only
entered the vestibule of the knowledge of natural phenomena and forces,
that it has but just begun to know five of the many stars, that “there
will come a time when our descendants will wonder that we were ignorant
of matters so evident.”[476]
[Sidenote: Study of nature as an ethical substitute for existing
religion.]
In one passage Seneca perhaps expresses his consciousness of the very
imperfect scientific knowledge of his own age a little too mystically.
“There are sacred things which are not revealed all at once. Eleusis
reserves sights for those who revisit her. Nature does not disclose her
mysteries in a moment. We think ourselves initiated; we stand but at
her portal. Those secrets open not promiscuously nor to every comer.
They are remote of access, enshrined in the inner sanctuary.”[477]
Indeed, he shows a tendency to regard scientific research as a sort of
religious exercise or perhaps as a substitute for existing religion
and a basis for moral philosophy. He relates physics to ethics. His
enthusiasm in the study of natural forces appears largely due to the
fact that he believes them to be of a sublime and divine character
and above the petty affairs of men. He also as constantly and more
fulsomely than Pliny inveighs against the luxury, vice, and immorality
of his own day, and moralizes as to the beneficent influence which
natural law and phenomena should exert upon human conduct. It is
interesting to note that this habit of drawing moral lessons from the
facts of nature was not peculiar to medieval or Christian writers.
[Sidenote: Limited field of Seneca’s work.]
With such subjects as zoology, botany, and mineralogy Seneca’s work has
little to do; it does not, like Pliny’s _Natural History_, include
medicine and the industrial arts; neither does he, like Pliny, cite
the lore of the _magi_. The phenomena of which he treats are mainly
meteorological manifestations, such as winds, rain, hail, snow, comets,
rainbows, and what he regards as allied subjects, earthquakes, springs,
and rivers. Perhaps he would not have regarded the study of vegetables,
animals, and minerals as so lofty and sublime a pursuit. At any rate,
in consequence of the restricted field which Seneca covers we find very
little of the marvelous medicinal and magical properties of plants,
animals, and other objects, or the superstitious procedure which fill
the pages of Pliny.
[Sidenote: Marvels accepted, questioned, or denied.]
Seneca nevertheless has occasion to repeat some tall stories, such as
that the river Alpheus of Greece reappears as the Arethusa in Sicily
and there every four years casts up filth from its depths on the very
days when victims are slaughtered at the Olympic games.[478] He also
affirms that living beings are generated in fire; he believes in
such effects of lightning as removing the venom from snakes which it
strikes; and he recounts the old stories of floating islands and of
waters with the virtue of turning white sheep black.[479] On the other
hand, he qualifies by the phrases, “it is believed” and “they say,” the
assertions that certain waters produce foul skin-diseases and that dew
in particular, if collected in any quantity, has this evil property;
and he doubts whether bathing in the Nile would enable a woman to bear
more children.[480] He ridicules the custom of the city which had
public watchmen appointed to warn the inhabitants of the approach of
hail-storms, so that they might avert the danger by timely sacrifice
or simply by pricking their own fingers so that they bled a trifle. He
adds that some suggest that blood may possess some occult property of
repelling storm-clouds, but he does not see how there can be such force
in a drop or two and thinks it simpler to regard the whole thing as
false. In the same chapter he states that uncivilized antiquity used to
believe that rain could be brought on or driven off by incantations,
but that now-a-days no one needs a philosopher to teach him that this
is impossible.[481]
[Sidenote: Belief in natural divination and astrology.]
But while he thus rejects incantations and is practically silent
on the subject of natural magic, Seneca accepts natural divination
in well-nigh all its branches: sacrificial, augury, astrology, and
divination from thunder. He believes that whatever is caused is a
sign of some future event.[482] Only Seneca holds that every flight
of a bird is not caused by a direct act of God, nor the vitals of the
victim altered under the axe by divine interference, but that all has
been prearranged in a fatal and causal series.[483] He believes that
all unusual celestial phenomena are to be looked upon as prodigies
and portents. A meteor “as big as the moon appeared when Paulus was
engaged in the war against Perseus”; similar portents marked the death
of Augustus and execution of Sejanus, and gave warning of the death of
Germanicus.[484] But no less truly do the planets in their unvarying
courses signify the future. The stars are of divine nature, and we
ought to approach the discussion of them with as reverent an air as
when with lowered countenance we enter the temples for worship.[485]
Not only do the stars influence the upper atmosphere as earth’s
exhalations affect the lower, but they announce what is to occur.[486]
Seneca employs the statement of Aristotle that comets signify the
coming of storms and winds and foul weather to prove that they are
stars; and declares that a comet is a portent of bad weather during
the ensuing year in the same way that the Chaldeans or astrologers say
that a man’s natal star determines the whole course of his life.[487]
In fact, Seneca’s chief, if not sole, objection to the Chaldeans or
astrologers would seem to be that in their predictions they take only
five stars[488] into account. “What? Think you so many thousand
stars shine on in vain? What else, indeed, is it which causes those
skilled in nativities to err than that they assign us to a few stars,
although all those that are above us have a share in the control of our
fate? Perhaps those which are nearer direct their influence upon us
more closely; perhaps those of more rapid motion look down on us and
other animals from more varied aspects. But even those stars that are
motionless, or because of their speed keep equal pace with the rest of
the universe and seem not to move, are not without rule and dominion
over us.”[489] Seneca accepts the theory of Berosus that whenever all
the stars are in conjunction in the sign of Cancer there will be a
universal conflagration, and a second deluge when they all unite in
Capricorn.[490]
[Sidenote: Divination from thunder.]
It is on thunderbolts as portents of the future that Seneca dwells
longest, however.[491] “They give,” he declares, “not signs of this or
that event merely, but often announce a whole series of events destined
to occur, and that by manifest decrees and ones far clearer than if
they were set down in writing.”[492] He will not accept, however,
the theory that lightning has such great power that its intervention
nullifies any previous and contradictory portents. He insists that
divination by other methods is of equal truth, though possibly of
minor importance and significance. Next he attempts to explain how the
dangers of which we are warned by divination may be averted by prayer,
expiation, or sacrifice, and yet the chain of events wrought by destiny
not be broken. He maintains that just as we employ the services of
doctors to preserve our health, despite any belief we may have in fate,
so it is useful to consult a _haruspex_. Then he goes on to speak of
various classifications of thunderbolts according to the nature of the
warnings or encouragements which they bring.
[Sidenote: Ptolemy.]
We pass on from Seneca to a later and greater exponent of natural
science and divination, Ptolemy, in the following century. He was
perhaps born at Ptolemaïs in Egypt but lived at Alexandria. The exact
years of his birth and death are unknown, and very little is recorded
of his life or personality. The time when he flourished is sufficiently
indicated, however, by the fact that his first recorded astronomical
observation was in 127 and his last in 151 A. D. Thus most of his
work was probably done during the reigns of Hadrian and Antoninus
Pius, but he appears to have lived on into the reign of Marcus
Aurelius. His strictly scientific style scorns rhetorical devices and
literary felicities, and while it is clear and correct, is dry and
impersonal.[493]
[Sidenote: His two chief works.]
Ptolemy’s two chief works, the _Geography_ in eight books, and ἡ
μαθηματικὴ σύνταξις, or _Almagest_ (al-μεγίστη) as the Arabs called
it, in thirteen books, have been so often described in histories of
mathematics, astronomy, geography, and discovery that such outline
of their contents need not be repeated here. The erroneous Ptolemaic
theories of a geocentric universe and of an earth’s surface on which
dry land preponderated are equally well known. What is more to the
point at present is to note that one of these theories was so well
fitted to actual scientific observations and the other was thought to
be so similarly based, that they stood the test of theory, criticism,
and practice for over a thousand years.[494] It should, however, be
said that the _Geography_ does not seem to have been translated into
Latin until the opening of the fifteenth century,[495] when Jacobus
Angelus made a translation for Pope Alexander V, (1409-1410), which is
extant in many manuscripts[496] as well as in print.[497] It therefore
did not have the influence and fame in the Latin middle ages that
the _Almagest_ did or the briefer astrological writings, genuine and
spurious, current under Ptolemy’s name.
[Sidenote: His mathematical method.]
We may briefly state one or two of Ptolemy’s greatest contributions
to mathematical and natural science and his probable position in the
history of experimental method. Perhaps of greater consequence in the
history of science than any one specific thing he did was his continual
reliance upon mathematical method both in his astronomy and his
geography. In particular may be noted his important contribution to
trigonometry in his table of chords, which modern scholars have found
correct to five decimal places, and his contribution to the science of
cartography by his successful projection of spherical surfaces upon
flat maps.
[Sidenote: Attitude towards authority and observation.]
Ptolemy based his two great works partly upon the results already
attained by earlier scientists, following Hipparchus especially in
astronomy and Marinus in geography. He duly acknowledged his debts
to these and other writers; praised Hipparchus and recounted his
discoveries; and where he corrected Marinus, did so with reason. But
while Ptolemy used previous authorities, he was far from relying upon
them solely. In the _Geography_ he adds a good deal concerning the
orient and northern lands from the reports of Roman merchants and
soldiers. His intention was to repeat briefly what the ancients had
already made clear, and to devote his works chiefly to points which had
remained obscure. His ideal was to rest his conclusions upon the surest
possible observation; and where such materials were meager, as in the
case of the _Geography_, he says so at the start. He also recognized
that delicate observations should be repeated at long intervals in
order to minimize the possibility of error. He devised and described
some scientific instruments and conducted a long series of astronomical
observations. He anteceded Comte in holding that one should adopt the
simplest possible hypothesis consistent with the facts to be explained.
[Sidenote: The _Optics_.]
Besides some minor astronomical works and a treatise on music which
seems to be largely a compilation an important work on optics is
ascribed to Ptolemy.[498] It is the most experimental in method of his
writings, although Alexander von Humboldt’s characterization of it as
the only work in ancient literature which reveals an investigator of
nature in the act of physical experimentation[499] must be regarded
as an exaggeration in view of our knowledge of the writings of other
Alexandrines such as Hero and Ctesibius. As in the case of some of
Ptolemy’s other minor works, the Greek original is lost and also
the Arabic text from which was presumably made the medieval Latin
version which alone has come down to us. Yet there are at least
sixteen manuscripts of this Latin version still in existence.[500]
The translation was made in the twelfth century by Eugene of Palermo,
admiral of Sicily, whose name is attached to other translations and
who was also the author of a number of Greek poems.[501] Heller
states that the _Optics_ was lost at the beginning of the seventeenth
century but that manuscripts of it were rediscovered by Laplace and
Delambre.[502] At any rate the first of the five books is no longer
extant, although Bridges thinks that Roger Bacon was acquainted with
it in the thirteenth century.[503] It dealt with the relations between
the eye and light. In the second book conditions of visibility are
discussed and the dependence of the apparent size of bodies upon the
angle of vision. The third and fourth books deal with different kinds
of mirrors, plane, convex, concave, conical, and pyramidical. Most
important of all is the fifth and last book, in which dioptrics and
refraction are discussed for the first and only time in any extant
work of antiquity,[504] provided the _Optics_ has really come down in
its present form from the time of Ptolemy. His authorship has been
questioned because the subject of refraction is not mentioned in the
_Almagest_, although even astronomical refraction is discussed in the
_Optics_.[505] De Morgan also objects that the author of the _Optics_
is inferior to Ptolemy in knowledge of geometry.[506] Possibly a work
by Ptolemy has received medieval additions, either Arabic or Latin,
in the version now extant; maybe the entire fifth book is such a
supplement. That works which were not Ptolemy’s might be attributed to
him in the middle ages is seen from the case of Hero’s _Catoptrica_,
the Latin translation of which from the Greek is entitled in the
manuscripts _Ptolemaei de speculis_.[507]
[Sidenote: Medieval translations of _Almagest_.]
If there is, as in other parallel cases, the possibility that the
medieval period passed off recent discoveries of its own under the
authoritative name of Ptolemy, there also is the certainty that it made
Ptolemy’s genuine works very much its own. This may be illustrated
by the case of the _Almagest_. On the verge of the medieval period
the work was commented upon by Pappus and Theon at Alexandria in the
fourth, and by Proclus in the fifth century. The Latin translation
by Boethius is not extant, but the book was in great repute among
the Arabs, was translated at Bagdad early in the ninth century and
revised later in the same century by Tabit ben Corra. During the
twelfth century it was translated into Latin both from the Greek and
the Arabic. The translation most familiar in the middle ages was
that completed at Toledo in 1175 by the famous translator, Gerard of
Cremona. There has recently been discovered, however, by Professors
Haskins and Lockwood[508] a Sicilian translation made direct from the
Greek text some ten or twelve years before Gerard’s translation. There
are two manuscripts of this Sicilian translation in the Vatican and
one at Florence, showing that it had at least some Italian currency.
Gerard’s reputation and his many other astronomical and astrological
translations probably account for the greater prevalence of his
version, or possibly the theological opposition to natural science of
which the anonymous Sicilian translator speaks in his preface had some
effect in preventing the spread of his version.
[Sidenote: The _Tetrabiblos_ or _Quadripartitum_.]
Of Ptolemy’s genuine works the most germane to and significant for
our investigation is his _Tetrabiblos_, _Quadripartitum_, or four
books on the control of human life by the stars. It seems to have
been translated into Latin by Plato of Tivoli in the first half of
the twelfth century[509] before _Almagest_ or _Geography_ appeared in
Latin. In the middle of the thirteenth century Egidius de Tebaldis,
a Lombard of the city of Parma, further translated the commentary of
Haly Heben Rodan upon the _Quadripartitum_.[510] In the early Latin
editions[511] the text is that of the medieval translation; in the
few editions giving a Greek text there is a different Latin version
translated directly from this Greek text.[512]
[Sidenote: A genuine reflection of Ptolemy’s approval of astrology.]
In the _Tetrabiblos_ the art of astrology receives sanction and
exposition from perhaps the ablest mathematician and closest scientific
observer of the day or at least from one who seemed so to succeeding
generations. Hence from that time on astrology was able to take
shelter from any criticism under the aegis of his authority. Not that
it lacked other exponents and defenders of great name and ability.
Naturally the authenticity of the _Tetrabiblos_ has been questioned
by modern admirers of Hellenic philosophy and science who would keep
the reputations of the great men of the past free from all smudge of
superstition. But Franz Boll has shown that it is by Ptolemy by a
close comparison of it with his other works.[513] The astrological
_Centiloquium_ or _Karpos_, and other treatises on divination and
astrological images ascribed to Ptolemy in medieval Latin manuscripts
are probably spurious, but there is no doubt of his belief in
astrology. German research as usual regards its favorite Posidonius as
the ultimate source of much of the _Tetrabiblos_, but this is not a
matter of much consequence for our present investigation.
[Sidenote: Validity of astrology.]
In the _Tetrabiblos_ Ptolemy first engages in argument as to the
validity of the art of judicial astrology. If his remarks in this
connection were not already trite contentions, they soon came to be
regarded as truisms. The laws of astronomy are beyond dispute, says
Ptolemy, but the art of prediction of human affairs from the courses
of the stars may be assailed with more show of reason. Opponents of
astrology object that the art is uncertain, and that it is useless
since the events decreed by the force of the stars are inevitable.
Ptolemy opens his argument in favor of the art by assuming as evident
that a certain force is diffused from the heavens over all things
on earth. If ignorant sailors are able to judge the future weather
from the sky, a highly trained astronomer should be able to predict
concerning its influence on man. The art itself should not be rejected
because impostors frequently abuse it, and Ptolemy admits that it has
not yet been brought to the point of perfection and that even the
skilful investigator often makes mistakes owing to the incomplete
state of human science. For one thing, Ptolemy regards the doctrine
of the nature of matter held in his time as hypothetical rather than
certain. Another difficulty is that old configurations of the stars
cannot safely be used as the basis of present day predictions. Indeed,
so manifold are the different possible positions of the stars and the
different possible arrangements of terrestrial matter in relation to
the stars that it is difficult to collect enough observations on which
to base rules of general judgment. Moreover, such considerations as
diversity of place, of custom, and of education must be taken into
account in foretelling the future of different persons born under the
same stars. But although for these reasons predictions frequently fail,
yet the art is not to be condemned any more than one rejects the art of
navigation because of frequent shipwrecks.
[Sidenote: Influence of the stars not inevitable.]
Nor is it true that the art is useless because the decrees of the stars
are inevitable. It is often an advantage to have previous knowledge
even of what cannot be avoided. Even the prediction of disaster serves
to break the news gently. But not all predictions are inevitable and
immutable; this is true only of the motion of the sky itself and events
in which it is exclusively concerned. “But other events which do not
arise solely from the sky’s motion, are easily altered by application
of opposite remedies,” just as we can in part remedy the hurt of wounds
and diseases or counteract the heat of summer by use of cooling things.
The Egyptians have always found astrology useful in the practice of
medicine.
[Sidenote: Astrology as natural science.]
Ptolemy next proceeds to set forth the natures and powers of the
stars “according to the observations of the ancients and conformably
to natural science.” Later, when he comes to the prediction of
particulars, he still professes “to follow everywhere the law of
natural causation,” and in a third passage he states that he “will omit
all those things which do not have a probable natural cause, which many
nevertheless scrutinize curiously and to excess: nor will I pile up
divinations by lot-castings or from numbers, which are unscientific,
but I will treat of those which have an investigated certainty
based on the positions of the stars and the properties of places.”
Connecting the positions of the stars with earthly regions,—it
is an art that fits in well with Ptolemy’s other occupations of
astronomer and geographer! The _Tetrabiblos_ has been called “Science’s
surrender,”[514] but was it not more truly divination purified and made
scientific?
[Sidenote: Properties of the planets.]
Taking up first the properties of the seven planets, Ptolemy associates
with each one or more of the four elemental qualities, hot, cold, dry,
and moist. Thus the sun warms and to some extent dries, for the nearer
it comes to our pole the more heat and drought it produces. The moon
is moist, since it is close to the earth and is affected by the vapors
from the latter, while its influence renders other bodies soft and
causes putrefaction. But it also warms a little owing to the rays it
receives from the sun. Saturn chills and to some extent dries, for it
is remote from the sun’s heat and earth’s damp vapors. Mars emits a
parching heat, as its color and proximity to the sun indicate. Jupiter,
situated between cold Saturn and burning Mars, is of a rather lukewarm
nature but tends more to warmth and moisture than to their opposites.
So does Venus, but conversely, for it warms less than Jupiter does
but moistens more, its large surface catching many vapors from the
neighboring earth. In Mercury, situated near sun, moon, and earth
alike, neither drought nor dampness predominates, but the velocity of
that planet makes it a potent cause of sudden changes. In general, the
planets exert a good or evil influence as they abound in the two rich
and vivifying qualities, heat and moisture, or in the detrimental ones,
cold and drought. Wet stars like the moon and Venus, are feminine;
Mercury is neuter; the other planets are masculine. The sex of a planet
may also, however, be reckoned according to its position in relation
to the sun and the horizon; and changes in the influences exerted
by the planets are noted according to their position or relation to
the sun. This discussion of the properties of the planets is neither
convincing nor scientific. It seems arguing in a circle to make their
effects upon the earth depend to such an extent upon themselves being
affected by vapors from the earth. Indeed we are rather surprised that
an astronomer like Ptolemy should represent vapors from the earth
as affecting the planets at all. But his discussion is at least an
effort, albeit a feeble one, to express the potencies of the planets in
physical terms.
[Sidenote: Remaining contents of Book One.]
Ptolemy goes on to discuss the powers of the fixed stars which seem to
depend upon their positions in constellations and their relations to
the planets. Then he treats of the influence of the four seasons of
the year and four cardinal points, each of which he relates to one of
the four qualities, hot, cold, dry, and moist. With a discussion of
the signs of the zodiac and their division into Houses and relation in
_Trigones_ or _Triplicitates_ or groups of three connected with the
four qualities, of the exaltation of the planets in the signs and of
other divisions of the signs and relations of the planets to them, the
first book ends.
[Sidenote: Book Two: Regions.]
The second book begins by distinguishing prediction of events for whole
regions or countries, such as wars, pestilences, famines, earthquakes,
winds, drought, and weather, from the prediction of events in the lives
of individuals. Ptolemy holds that events which affect large areas or
whole peoples and cities are produced by greater and more valid causes
than are the acts of individual men, and also that in order to predict
aright concerning the individual it is necessary to know his region
and nationality. He characterizes the inhabitants of the three great
climatic zones,[515] quarters the inhabited world into Europe, Libya,
and two parts for Asia in the style of the T maps, and subdivides these
into different countries whose peoples are described, including such
races as the Amazons. The effects of the stars vary according to time
as well as place, so that the period in which any individual lives is
as important to take into account as his nationality. Ptolemy also
discusses how the heavenly bodies influence the _genus_ of events, a
matter which depends largely upon the signs of the zodiac, and also
how they determine their quality, good or bad, and species, which
depends on the dominant stars and their conjunctions. Consequently he
gives a list of the things which belong under the rule of each planet.
The remainder of the second book is concerned chiefly with prediction
of wind and weather through the year and with other meteorological
phenomena such as comets.
[Sidenote: Nativities.]
The last two books take up the prediction of events in the lives of
individuals from the stars, in other words the science of nativities
or genethlialogy. The third book discusses conception and birth,
how to take the horoscope—Ptolemy insists that the astrolabe is the
only reliable instrument for determining the exact time; sun-dials
or water-clocks will not do—and how to predict concerning parents,
brothers and sisters, sex, twins, monstrous births, length of life, the
physical constitution of the child born and what accidents and diseases
may befall it, and finally concerning mental traits and defects. The
fourth book deals less with the nature of the individual and more with
the prediction of external events which befall the individual: honors,
office, marriage, offspring, slaves, travel, and the sort of death that
he will die. Ptolemy in opening the fourth book makes the distinction
that, while in the third book he treated of matters antecedent to birth
or immediately related to birth or which concern the temperament of the
individual, now he will deal with those external to the body and which
happen to the individual from without. But of course it is difficult to
maintain such a distinction with entire consistency.
[Sidenote: Future influence of the _Tetrabiblos_.]
The great influence of the _Tetrabiblos_ is shown not only in medieval
Arabic commentaries and Latin translations, but more immediately in
the astrological writings of the declining Roman Empire, when such
astrologers as Hephaestion of Thebes,[516] Paul of Alexandria, and
Julius Firmicus Maternus cite it as a leading authoritative work. Only
the opponents of astrology appear to have remained ignorant of the
_Tetrabiblos_, continuing to make criticisms of the art which do not
apply to Ptolemy’s presentation of it or which had been specifically
answered by him. Thus Sextus Empiricus, attacking astrology about
200 A. D., does not mention the _Tetrabiblos_ and some of the
Christian critics of astrology apparently had not read it. Whether the
Neo-Platonists, Porphyry and Proclus, wrote an introduction to and
commentary upon it is disputed.