drawings and engravings such as Battle of the Nude Men
(c. 1470) exemplify the link between art and research into
nature that was to be such a feature of Leonardo’s work. In
this engraving and in Pollaiuolo’s masterpiece, the Mar-
tyrdom of St. Sebastian (1475; National Gallery, London),
the figures have clearly defined muscular structures and
the pictures are composed to show poses from a variety of
angles.
Pollaiuolo’s second main innovation was the intro-
duction of landscape interest to Florentine art through
paintings such as Hercules and Nessus (Yale Art Gallery,
New Haven), which set the figures in a lyrical landscape.
His most important sculptures were carried out with Piero
in St. Peter’s in the 1490s. They are the bronze tombs of
Sixtus IV (1493) and of Innocent VIII (c. 1495). The lat-
ter included the first sepulchral effigy to depict the living
man, and features of both tombs were widely copied.
Further reading: Leopold D. Ettlinger, Antonio and
Piero Pollaiuolo (Oxford, U.K.: Phaidon and New York:
Dutton, 1978).
Pollaiuolo, Simone del See CRONACA, SIMONE, IL
Polybius (c. 202–120 BCE) Greek historian
Polybius had a distinguished career in Greek public life,
was the friend of the great Roman general Scipio Aemil-
ianus, and after 146 BCEorganized the Roman adminis-
tration in Greece. His wide military and diplomatic
experience made him exceptionally well qualified to ob-
serve and discuss the causes of Rome’s rise and the deca-
dence of the Greek cities. Much of his narrative and
viewpoint in the first five books of his History (all that sur-
vive intact out of the original 40) was exceptionally inter-
esting to Renaissance students of statecraft, warfare, and
the role of the individual in history. Fragments of the sixth
book survive in excerpts, including a passage on the
Roman constitution that appears to have influenced
MACHIAVELLI. A Latin translation, made in 1452–53 for
Pope Nicholas V, was printed in 1473, and the editio prin-
ceps appeared in 1530.
Pomponazzi, Pietro (1462–1525) Italian physician and
philosopher
Pomponazzi was born at Mantua. After medical studies at
Padua (1487) he was appointed professor of philosophy
there and lectured on Aristotle’s Physics until 1509, when
the closure of the Paduan schools sent him to Ferrara.
There he began the studies in Aristotelian psychology
which were to lead him to develop heretical views con-
cerning the nature of the soul. In 1512 he went to Bologna
as professor of natural and moral philosophy, a post which
he held until his death. In 1516 he published De immor-
talitate animae, a treatise on the immortality of the soul
that generated much opposition, as it conflicted with both
the accepted (Thomist and Averroist) views on Aristotle.
Pomponazzi tried to separate his speculations from his
own personal belief and made a formal submission to the
Church on matters of faith, but it required the interven-
tion of Cardinal BEMBOwith Pope Leo X to save him from
suffering as a heretic.Ponce de León, Juan (1474–1521) Spanish explorer,
conquistador, and administrator
Having fought against the Moors of Granada, he volun-
teered for COLUMBUS’s 1493 West Indian voyage. In 1502
he joined another West Indies expedition and in 1506 led
the subjugation of present-day Puerto Rico. Following a
spell as a colonial governor (1509–12), he sailed in search
of the mythical island of Bimini with its Fountain of
Youth, and in March 1513 made landfall in the land he
named Florida. His ship’s log of this voyage (now lost) was
used by the historian Antonio de Herrera (1559–1625)
in his Historia general de los hechos de los castellanos en
las islas i tierra firme del Mar Océano (1601–15). After
five years (1515–20) in Puerto Rico, he sailed again for
Florida but suffered a fatal arrow wound en route and died
in Havana.Pontano, Giovanni (1422–1503) Italian humanist
statesman and poet
Educated in his native Umbria, he entered the service of
the Aragonese king of Naples, ALFONSO I, becoming a
royal secretary. Under his successor FERDINAND I(Fer-
rante), Pontano was appointed secretary of state (1486)
and played a leading role in the political and military af-
fairs of the kingdom until the conquest by the French
under Charles VIII (1495).
Early in his career Pontano had become a dominant
influence in the NEAPOLITAN ACADEMYand acted as its of-
ficial head from 1471. His devotion to classical learning,
which led him to adopt the name Jovianus (or the Italian-
ized form, Gioviano) Pontanus, inspired his many and
varied Latin works in prose and verse. His prose works in-
clude a number of stories and essays or dialogues, often
on conventional moral subjects (generosity, fortune, etc.)
and on philology and astrology; and a history, De bello
napoletano, on the war between the French and the house
of Aragon. His poetry was held by some contemporaries,
among them Erasmus, to rival or surpass its classical mod-
els, such as Theocritus and Virgil. It includes three PAS-
TORALeclogues (Acon, Quinquennius, Maeon) and three
idylls (Meliseus, Lepidina, Coryle), published by the Aldine
press in 1518, that greatly influenced the revival of inter-
est in classical pastoral verse in the Renaissance.Pontelli, Baccio (1450–c. 1492) Italian architect
Pontelli, who was born in Florence, first trained as a
woodcarver and worked in the cathedral in Pisa and in
Urbino. He probably learned the technique of castle con-
struction from FRANCESCO DI GIORGIO MARTINIand duringPPoonntteellllii,, BBaacccciioo 3 38877