wrote poetry and plays and in his prose works, many of
them polemics against the Calvinists, he strove to improve
the quality of his native language. Zedekunst (1586) is
modeled on the ethical treatises of the ancient Stoics. He
also began, but left incomplete, a Dutch version of the
New Testament.
Copernican system The cosmological scheme advanced
in COPERNICUS’s De revolutionibus (1543), contrary to the
traditional geocentric astronomy of Ptolemy (see PTOLE-
MAIC SYSTEM). In the Copernican system the universe is
centered upon the sun, around which the earth and all
other celestial bodies revolve with uniform motion in per-
fectly circular orbits; in addition the earth rotates daily
around its own axis (see illustration p. 121). In this sim-
ple manner Copernicus accounted for the observed rota-
tion of the heavens by the daily movement of just one
body. Many, however, considered it most implausible to
suppose that the earth could move in such a manner.
Buildings would collapse, it was objected, and stones
dropped from a hand would not fall directly to the ground.
Cavils of this kind continued to be raised for some time;
until, in fact, they were only dispeled by the better analy-
sis of the nature of motion offered by GALILEOand his suc-
cessors.
On the matter of planetary orbits, however, Coperni-
cus appears less innovatory. Like Ptolemy, he assumed
without question that planets moved in circular orbits
with a uniform velocity. Such a theory is far too simple to
describe the planets’ paths as they move in their elliptical
orbits with their varying velocities. Thus, to account, for
example, for their variable velocities and their constantly
changing distances from the sun, Copernicus found it
necessary to locate each of the planets on its own epicycle.
In this way he found himself as dependent upon ec-
centrics and epicycles as any Ptolemaic astronomer. It has
been calculated that he actually increased the number of
such constructions from the 40 of the Almagest to the 48
found in De revolutionibus. Complications of this kind per-
sisted in ASTRONOMYuntil the time of KEPLERand his real-
ization that planets moved in elliptical orbits.
Damaging theological objections remained. In the
Bible Joshua, for instance, had commanded the sun, not
the earth, to stand still (Joshua 10:12–13). Consequently,
in 1616 the Holy Office placed De revolutionibus on the
INDEX LIBRORUM PROHIBITORUM, where it remained until
- Kepler’s Epitome astronomiae Copernicanae met a
similar fate in 1619.
Further reading: Owen Gingerich, The Eye of Heaven:
Ptolemy, Copernicus, Kepler (Berlin: Springer Verlag,
1993); Thomas S. Kuhn, The Copernican Revolution (Cam-
bridge, Mass.: Harvard University Press, 1966; repr.
1992).
Copernicus, Nicolaus (1473–1543) Polish astronomer
The son of a merchant, Copernicus was born at Torun and
educated at Cracow university and at various Italian uni-
versities where he studied medicine and law. On his return
to Poland in 1506 he served as physician and secretary to
his uncle Lucas, Bishop of Ermland. On his uncle’s death
(1512), Copernicus took up the post of canon of Frauen-
burg cathedral to which he had been appointed in 1499.
By this time he had already abandoned the traditional as-
tronomy of antiquity (see PTOLEMAIC SYSTEM) and had
begun to formulate the revolutionary system with which
his name has been associated (see COPERNICAN SYSTEM).
The new system was first described in his Commentariolus,
a brief tract completed sometime before 1514 and circu-
lated in manuscript to interested scholars. Thereafter he
worked out the details of the new system in an exact and
comprehensive manner in his De revolutionibus orbium
coelestium (1543; translated as Concerning the Revolutions
of the Heavenly Spheres, 1952). Although it was complete
in manuscript by 1530 Copernicus seemed, for no very
clear reason, reluctant to publish his work. It was not, in
fact, until RHETICUSarrived in Frauenburg in 1539 and in-
tervened that Copernicus reluctantly allowed its publica-
tion. The work finally appeared just in time, according to
popular legend, for it to be shown to Copernicus on his
deathbed.
There were several other dimensions to the career of
Copernicus. For much of his life Poland was under threat
from the TEUTONIC KNIGHTSand Copernicus found him-
self on more than one occasion besieged by them and
called upon to negotiate with them. He also, in his De
monete (1522), wrote on the topic of Poland’s debased cur-
rency, and, according to some scholars, is to be credited
with the first formulation of the principle, later known
as Gresham’s law, that “bad money drives out good” (see
GRESHAM, SIR THOMAS).
De revolutionibus orbium coelestium was first printed at
Nuremberg in 1543 and republished during the Renais-
sance at Basle (1566) and Amsterdam (1611). There are
facsimiles of the 1543 edition (Amsterdam, 1943) and of
the 1566 Basle edition (Prague, 1971); the latter is edited
by Z. Horský and contains Tycho Brahe’s commentary on
Copernicus’s work, as well as an introduction and notes in
Czech, English, French, German, and Russian. There is an
annotated English translation by A. M. Duncan, On the
Revolutions of the Heavenly Spheres (Newton Abbot, U.K.,
1976). A more recent translation is that by Charles G.
Wallis, published in the Great Minds series by Prometheus
Books (1995).
Further reading: Owen Gingerich and Robert S.
Westman, The Wittich Connection: Conflict and Priority in
Late Sixteenth-century Cosmology (Philadelphia, Penn.:
American Philosophical Society, 1988); Fred Hoyle, Nico-
laus Copernicus: An Essay on His Life and Work (London:
Heinemann, 1973).11118 8 CCooppeerrnniiccaann ssyysstteemm