Naturalism. If one considers the frequent polemics
that the humanists conducted against the study of
physics, and particularly that of Aristotle, humanism
would appear to be an antinaturalism. In his De
nobilitate legum et medicinae Coluccio Salutati put the
study of law, which concerns men and their interrela-
tions, above that of medicine, and in general above
the sciences of nature, which are concerned with
things. In the Isagogicon moralis disciplinae Leonardo
Bruni asserted that those who passed over moral phi-
losophy and devoted themselves, on the contrary, to
physical science, seemed, so to speak, to be occupied
with matters that are foreign to them while neglecting
those that are close. Analogous ideas were expressed
by Matteo Palmieri in his work Della vita civile (ca.
1440) and Bartolommeo de' Sacchi in De optimo cive.
All these humanists contrast the “moral Aristotle” with
the “physical Aristotle.” The same Leonardo Bruni
translated from Greek into Latin the Nicomachean
Ethics, the
Politics, and the
Economics of Aristotle, with
the polemical purpose of calling attention to that part
of Aristotle's work that deals precisely with man and
his life in society and which had been neglected or
even ignored by the medieval writers.
But this polemical attitude did not prevent the
humanists from finding, translating, or retranslating,
and circulating the basic texts of ancient science. The
De medicina of Celsus (42 B.C.-A.D. 37), unknown in
the Middle Ages, had just been discovered in 1426 by
Guarino and was then widely circulated and studied
(printed in 1476, English trans., 1876). It was quoted
by Leonardo da Vinci. The writings of Hippocrates
and Galen were, still in the fifteenth century, retrans-
lated and provided with commentaries. The works of
Archimedes already circulated in Greek in the first
decades of the fifteenth century and were translated
towards the middle of the century. From these works
Galileo obtained decisive inspiration for his own work.
Precisely through the knowledge of these texts, pro-
vided by the humanists, the renewal of science was
being prepared. “Endeavoring to see in nature what
Greek writers had declared to be there, European
scientists slowly came to see what really was there”
(Marie Boas, p. 49).
At the same time the flowering of painting with its
new perspective, of architecture, and of craftsmanship
in many forms and refinements, demonstrated the
increasing search for new techniques and for the
knowledge which was indispensable for putting them
into practice. The ideal approach towards art, in that
period, and towards the Renaissance itself, is charac-
terized by a return to nature, in contention against the
stereotyped symbolic forms of medieval art; that is,
by a tendency to seek in nature and to represent in
art the authentic aspects of nature herself, no longer
mediated by the symbolic-linguistic forms that the
Middle Ages had used.
However, the same Renaissance Aristotelianism that
had flourished between 1400 and 1600, above all in
the school of Padua, drew its sustenance from the texts
rescued by the humanists, and from their researches
and contributions to the affirmation of scientific
naturalism; especially in their refusal to admit the
possibility of miracles, and their insistence on the nec-
essary order which governs all natural objects.
But notwithstanding the polemics against the study
of Aristotelian physics, a study which the humanists
thought of as a piétiner sur place (“marking time”) and
incapable of leading to knowledge that was really new
and useful to man, Italian Renaissance humanism can
be considered as a naturalism in the most exact sense
of the term, i.e., the belief that man is not a casual
guest of the natural world but must make of this world
his home and thereby recognize that the fundamental
needs of his life bind him to it. The humanists in
general did not deny the transcendent end of man, his
supernatural life and beatitude. But they set up a new
evaluation of man's needs and of the relations that bind
him to nature, and hence they tried from this point
of view to modify radically the scale of moral values.
The De voluptate (1431) of Lorenzo Valla is the basic
document concerning this point. The thesis of the work
is that only pleasure is the authentic good of man and
that all the other goods can be reduced to pleasure.
It is the end that nature herself has indicated to man,
furnishing him also with the means of obtaining it.
External goods, like riches, health, honor, power, are
desirable only because of their being sources of pleas-
ure. Music, song, wine are sources of pleasure that one
need not depreciate; and vice is an evil because it does
not leave the soul in peace but disturbs it by the
memory of that which has been done. The heroic
sacrifices of which both ancients and moderns speak
have also been made for pleasure; because he who is
placed in the impossibility of finding it seeks at least,
in subordinate order, to avoid the pain of its privation.
Glory and contemplative life are likewise desired for
the pleasure that they confer. And Valla does not
hesitate to say that “courtesans and harlots are more
deserving of humankind than holy and chaste virgins”
(De voluptate, I). On pleasure is founded human
solidarity itself, because since the origins of humanity
no one has desired or seen with joy another's evil, but
on the contrary has desired the good of another and
has rejoiced when it has befallen him. One can miscal-
culate all this and desire something that seems to be
a pleasure both for oneself and others, and then reveals
itself on the contrary to be a pain and an evil. But
the error can be avoided by prudent calculation.
These ideas of Lorenzo Valla have inspired a vast
humanistic literature in which the polemic against
asceticism, held to be one of the basic values in medie-
val life, was united to a reevaluation of Epicurus,
whose doctrine was believed in the Middle Ages to
be synonymous with impiety and immorality, and
whom on the contrary the humanists recognized as a
true master of human wisdom. “Epicurus,” said Cosma
Raimondi, “put the highest good in pleasure because
he examined more deeply the force of nature and
understood that we have been formed by nature in such
a way that nothing is more akin to us than having all
the members of the body whole and healthy and pre-
serving them in this condition without being affected
by any spiritual or corporeal evil.”
When one contrasts the literary and rhetorical char-
acter of humanism with the scientific interest which
had animated certain scholastics of the fourteenth cen-
tury (John Buridan, Nicolas of Oresme, Albert of
Saxony), and from this comparison concludes that there
was a retarding action of humanism on natural science,
which would have been better promoted by these
Scholastics, an important fact is neglected: the Scho-
lasticism of the fourteenth century derives its interest
from being a
critique of traditional Aristotelianism, and
from having initiated its dissolution. The theory of
impetus which Buridan applied to the motion of the
heavens and which thus rendered useless the moving
intelligence assumed by Aristotle to explain this mo-
tion; the doubts of Nicolas of Oresme expressed in his
Commentario (ca. 1377) on the
De caelo, on the entire
Aristotelian cosmology; and in general the empiricist
and critical orientation which the major Scholastics of
the fourteenth century showed in their Aristotelian
commentaries, constituted decisive attacks on the au-
thority of Aristotle. But it is precisely against this
authority that the humanists' criticism was directed.
The
Dialecticae disputationes (1439) of Lorenzo Valla
attacked the Scholastics who accepted supinely the
authority of Aristotle and induced their pupils to swear
not to discuss him. These, says Valla, are superstitious
and nonsensical men who depreciate their own merits
and deprive themselves of the faculty of seeking the
truth. That which, in the Scholasticism of the four-
teenth century, indicated the beginning of an inde-
pendent investigation of the natural world, found a
support, not an obstacle, in the humanistic
critique of
Aristotle.
We must finally recall that the first steps of modern
science were taken by Copernicus, Kepler, and Galileo
and were guided by the belief that nature has a mathe-
matical order or, as Galileo says, “The book of nature
is written in mathematical characters.” This belief is
an integral part of the Platonic tradition which the
humanists brought back to life. And it was this belief
which inspired the work of Leonardo da Vinci, who
called himself “a man without letters,” whose only
intention was to read “the book of nature.” He main-
tained that this book could be read only by consulting
experience directly and that through experience can
be discovered the reason which operates in nature, a
reason that is made manifest in immutable laws which,
however, can be interpreted and understood only in
terms of number, weight, and measure (numero,
pondere, et mensura).
On the other hand the sympathy that the humanists
showed for magic was inspired especially by the active
or operative character of the magical practices, i.e.,
of their capacity for intervening in natural events,
putting them, to a certain extent, under the control
of man.
Most probably without the proclamation of the
humanists that man is part of nature and that in her
we must live and work; without the close connection
that humanism established between man and his
worldly activity, and not only with literature and art,
but also with the crafts and daily labor, the empirical
investigation of nature which avails itself primarily of
direct observation would not have been initiated, or
would have been initiated only much later. The scho-
lastic doctors, at whom the humanists shot their arrows,
made many fine speeches on cosmology and Aristotel-
ian physics, but did not put a hand to operations of
research. The polemic of Galileo against “the paper
world” of the Aristotelians, which gave rise to modern
science, continued and carried to its legitimate conclu-
sion the battle of the humanists.
