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Dictionary of the History of Ideas

Studies of Selected Pivotal Ideas

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1. Humanism and the Universal Man. Most (but not
all) of the complete personalities Burckhardt referred
to had been educated in the classical, humanistic
learning of their time. Burckhardt noted that the
learning of the universal man was no longer identified
with the encyclopaedic knowledge of the medieval
thinker, but he did not establish a connection between
humanism and the rise of the many-sided or all-sided
man. He did not credit humanism with fashioning an
ideal of the complete man nor with providing a curric-
ulum appropriate to it. If anything, he tended to be-
lieve that no such objective was entertained by those
who would seem to have striven to fulfill it.

It was an English historian of Renaissance classical
education who showed that the full development of
the personality which Burckhardt described corre-
sponded to the avowed objectives of humanist
educators. William Harrison Woodward's Vittorino da
Feltre and Other Humanist Educators
(1897) is based
upon a close study of the famous teacher and upon
humanistic treatises on education (many of which he
translated and published in this work). He found in
these writings, as in Vittorino's teaching, a conscious
revival of both the ancient rhetorical tradition of gen-
eral education (encyklios paideia) and its underlying
ideal of the whole man. Vittorino called his method
of education “encyclopaedic,” by which he meant a
balanced combination of intellectual, moral, and phys-
ical training. Another humanist educator, Battista
Guarino, explicitly identified humanistic learning with
Greek paideia and Roman humanitas; and Maffeo
Vegio, in a treatise De educatione liberorum (ca. 1460),
hailed the humanistic restoration of the “universal”
education of the ancients (qui orbis doctrinarum appel-
latus est

In point of fact, humanistic education was far from
universal or encyclopaedic in the sense of all-en-
compassing. If anything, it represents a narrowing
of the Seven Liberal Arts of medieval secondary edu-
cation. It dropped the mathematical Quadrivium
(arithmetic, geometry, music, astronomy) and deleted
logic from the literary Trivium (grammer, rhetoric,
dialectics). But it greatly expanded the study of “let-
ters” by adding poetry, history, and moral philosophy
(which was understood as a form of eloquence) to
grammar and rhetoric, as well as by adding Greek to
Latin letters (Kristeller, 1961, 1965). The Renaissance
studia humanitatis was thus strictly literary and clas-
sical; but founded as it was upon the tradition of
classical eloquence, it revived and adopted the ancient


rhetorical ideas of general education. Its guiding prin-
ciple was the ideal of classical humanitas: cultivation
of “the whole man, body and soul, sense and reason,
character and mind” (Marrou, 1948).

This “general” education (general because it was
neither technical nor professional in nature) was re-
garded by the humanists as the finest preparation for
public and private life. Bearing out Burckhardt's de-
scription of the union of theory and practice in the
humanists, Woodward noted the humanistic conviction
that the practical ends of the individual and society
would be furthered by a general, i.e., liberal education.
On the one hand, humanistic learning (particularly in
the secondary schools) was directed toward formation
of the person. The desire for distinction was encour-
aged by the humanists as a stimulus to learning, and
distinction required not only intellectual culture but
virtue, the cultivation of character, and the acquisition
of certain personal and social graces as well: eloquence,
dignity of bearing, accomplishment in various forms
of recreation and diversion. Moreover, the studia
was to lead to the perfection of man as
a political being (as citizen, courtier, or ruler, as the
case may be). In this regard, the union of scholarly
and practical interests was built into the very system
of humanistic studies which is directed simultaneously
toward thought and action: literature and society, po-
etry and history, rhetoric and moral philosophy—all
were necessary for the complete man. Finally, classical
studies provided authorities for a wide range of matters
of social and public concern, from statecraft (Aristotle's
Politics) to management of a household (Plutarch and
Cicero), from agriculture (Vergil) to the art of war

The humanists thus appear to be directly responsible
for popularizing the ideal of the well-rounded man.
And formal education was not their only instrument
for propagating and diffusing this ideal. They promoted
it in their writings as well; universalizing the general,
literary culture of the ancient orator, the humanists
recommended it (as P. O. Kristeller has pointed out)
in treatises addressed to diverse groups in Renaissance
society, to princes and citizens, to women, courtiers,
and artists—to all who professed “humanity.” Several
of Alberti's works exemplify this tendency, as does
Baldassare Castiglione's Il cortigiano (1528). Castig-
lione required the courtier to join to his customary
martial virtues and to his loyalty to his prince the
humanistic virtues of eloquence, a literary education,
and a certain accomplishment in painting, music, and
dancing. In the same spirit, although written a century
earlier and with a bourgeois audience in mind, Alberti's
De familia (ca. 1434) sets forth, in the idealized figures
of his own prominent merchant-banking family, a har
monious marriage of classical culture with the political,
economic, and social concerns of the urban patriciate.
One of his late works gives the reverse of this picture.
The subject of De iciarchia (1469) is the public respon-
sibilities (chiefly educational) of the humanist scholar.
Alberti also extended to the artist this conception of
the whole man. In De pictura (1435) he urged the
painter to become literate and acquire a general edu-
cation. This first treatise on painting was also the first
work to encourage development of that wide range
of interests and general competence which in fact came
to characterize the Renaissance artist.

The learning embraced by the artistic exponents of
the humanistic ideal was not always, and not even
typically, classical and literary, however. Alberti and
Leonardo, the two whom Burckhardt singled out as
most fully representative of his all-sided man, achieved
their universality outside the confines of humanistic
learning, as did Michelangelo who seemed to his age
the truly universal artist of all time. Alberti was a
humanist, to be sure. He was in fact the epitome of
the Renaissance humanist, animated as he was by the
desire to achieve that personal excellence which tri-
umphs over human frailty, death, and time, and bend-
ing all his liberal learning at the same time to practical
and social needs in characteristically humanistic fash-
ion. Alberti the Latinist wrote vernacular dialogues on
moral philosophy for the non literatissimi cittadini of
the lay society of his time; and it was for the sake
of justifying this use of the Tuscan tongue as an instru-
ment of learning and prose literature that he worked
out its first grammar. For the crafts of painting and
sculpture he provided a theoretical basis and, by
grounding them in the “sciences” of perspective and
anthropometry, drew them into the circle of the liberal
arts. Complementing this work, he applied the mathe-
matical learning of the schools, and his humanistic
knowledge of Ptolemy and Vitruvius, to problems of
surveying, map-making, and the construction of
measuring devices and simple machines. For a friend
who was a Papal Secretary, he devised the method of
coding by means of a cipher-wheel and of decoding
by frequency analysis. And for architects and builders,
he set forth in his famous De re aedificatoria (1452)
the engineering knowledge of antiquity and his own
day, the rules of classical architecture, and a theory
of universal Harmony which formed the aesthetic out-
look of his age and fostered its quest for propor-

This quest for proportionality, however, which was
at once an aesthetic, a scientific, a moral, and a meta-
physical objective, as Alberti's writings attest, bespeaks
a mathematical rather than a humanistic treatment of
problems. It belongs to a current of thought which is


just as fundamental to Renaissance culture as humanism
but is logically distinct from it. Alberti embodies both
currents, as did the classical culture of antiquity. His
Platonic conviction that the intellectual should serve
as guide and teacher of his age gave an ethical, a
humanistic consistency to the diversity of his works.
But methodologically, once he moved outside the
sphere of literature, philology, and moral philosophy
to accomplish this task, mathematics became the
organon of all his undertakings. It was by holding to
a mathematical intuition of reality (which he recovered
from classical sources), by working it out in a variety
of technical problems (often in accordance with clas-
sical exemplars) that Alberti's thought developed in
several fields of learning—fields which were hitherto
quite disparate, but in which he, and Leonardo after
him, brought about a new methodological unity and
achieved a new, nonliterary kind of universality.

2. Mathesis Universalis. Recent studies of Leonar-
do's thought have tended to find the basis of Leonar-
do's universality in his distinctive fusion of mathe-
matics and sensory experience. Ernst Cassirer (1927),
Ludwig H. Heydenreich (1944), Erwin Panofsky
(1953), V. P. Zubov (1962), and Eugenio Garin (1965)
all stress the significance of Leonardo's geometric
formulation of technical and physical problems in ac-
counting for the scope and unity of his thought. This
also holds true for Alberti's artistic and scientific work.
Burckhardt was right in maintaining that Leonardo
brought to fulfillment what Alberti had begun, for
Alberti and Leonardo are very much akin. They were
both practicing artists, practicing surveyors and map-
makers, practicing engineers. Both figure in the history
of astronomy, geography, mechanics, anatomy, optics,
and perspective. Leonardo's chief art was painting,
of course, whereas Alberti's was architecture; and
Leonardo brought his mathematical vision to bear on
a greater variety of problems than Alberti did and he
penetrated them more deeply; but both had the same
intention of discovering in the world of experience its
lawful, proportional structure. This was the methodo-
logical objective that made it possible for them to unite
art and science, and theory and practice, as they did.
The diversity of their interests sprang in both cases
from a commitment to practice and experience, “the
common mother of all the sciences and arts”
(Leonardo, ed. Richter, I, # 18). And both used mathe-
matics in the several arts and sciences they pursued
as the instrument by which to grasp the rational prin-
ciples of experience. If the studia humanitatis may be
regarded as a revised and expanded Trivium, the disci-
plines comprehended by Alberti and Leonardo repre-
sent a Quadrivium systematically expanded to include
all the sciences of measurement.

Alike as they are in their artistic and scientific
pursuits, however, Alberti and Leonardo did not share
the same “universe” of learning. It is not simply that
Leonardo's thought includes sciences such as botany,
zoology, geology, and hydraulics which are either not
found at all, or found only in very rudimentary form,
in Alberti. What is more remarkable is Leonardo's utter
disregard of humanistic values and the classical, literary
method of humanistic study. Leonardo was, as he
confessed, an omo sanza lettere. But his disinterest in
the studia humanitatis and his strictures against book-
learning cannot be accounted for solely by the fact
that he was trained as an apprentice in a workshop
rather than educated, as Alberti was, in a humanistic
gymnasium. Self-taught in almost everything he did,
Leonardo would have mastered the humanistic learning
of the time had he been vitally interested in it. He
did teach himself Latin, in fact, when he was forty-two,
but he used it to gain access to the physical knowledge,
not the literary culture of antiquity and the Middle
Ages. The humanistic mode of learning was alien to
him because, as his work and statements prove, the
kind of knowledge he sought was to be found in nature,
not books. He restricted himself quite deliberately to
sperienza (by which he meant chiefly visual experi-
ence), having won from its mathematical analysis, so
he thought, the rare prize of certain knowledge.

This divergence between humanism and what was
to become in the scientific academies of the seven-
teenth century an independent, empirical-mathemat-
ical mode of inquiry, is not yet felt in Alberti. In many
respects, technical and empirical thought was still
more primitive in the early fifteenth century than it
had been in antiquity, so that Alberti found many
of his most fruitful technical ideas in the classical
authors. Moreover, his humanistic ideas mingle with
his artistic and mathematical ones at the deeper level
of his fundamental intuition of the world and man. The
idea of proportion which figures in his thought as an
ideal of morality and mores—an idea that echoes
Cicero's notion of decorum and Plato's idea of justice—
complements his vision of the “outer” world of nature.
Balance, measure, or proportion in man reflects the
definition Alberti gave of cosmic beauty, that natural
“Harmony of all the parts, in whatsoever subject it
appears, fitted together with such proportion and con-
nection that nothing can be added, diminished, or
altered but for the worse” (De re aedificatoria IX, 5).
Alberti's successor knew nothing of this vital bond
between the moral and the physical world, between
man and nature. The proportion or measure that con-
stitutes the form of both the inner and outer world
in Alberti's thought is metaphysically conceived, of
course, and Leonardo, who developed and sharpened


the empirical-mathematical method he shared with
Alberti, evidently could not admit this conception into
his thought. With Leonardo's greater awareness of his
distinctively “scientific” methods and objectives, the
two currents of thought that Alberti held together in
one view of man and the world parted ways.

The humanistic movement also encouraged this sep-
aration. In contrast to early humanistic treatises on
education which included mathematics, dialectics, and
astronomy in their ideal curricula, the humanistic cur-
riculum of the late fifteenth and sixteenth centuries
came to be strictly defined as a program of literary,
historical, and ethical studies. The artistic-technical
interests of an Alberti could not be an integral part
of this studia humanitatis any more than the investi-
gation of nature could be pursued by means of litera-
ture. Humanism and the natural-scientific mode of
thought were found to follow different methodological
principles, and this intellectual fact shaped the specific
“universality,” i.e., the particular completeness and
comprehensive content of thought, of the two main
examples of the Renaissance universal man.

3. The Universal Man in Renaissance Society.
Different as they may be in method and objectives,
humanism and empirical-mathematical thought are
alike in their departure from the Scholastic form of
medieval universality. For sheer comprehensiveness,
neither the studia humanitatis nor the sciences of
measurement embraced by an Alberti or a Leonardo
can compete with Roger Bacon's proposed encyclo-
paedia of knowledge or the Summa Theologiae of
Thomas Aquinas. The two forms of Renaissance learn-
ing are limited, first to the world of experience, then
to the domain of either physical or cultural and social
experience. But with this narrowing of scope came a
rational grounding of knowledge. The principles of
thought in the humanities and natural sciences are
positive; those of the Scholastic organization of knowl-
edge are metaphysical and theological. Roger Bacon
intended to unify the sciences of his encyclopaedia by
placing them in the service of theology; and the
Summa Theologiae, as its name declares, is a work of
metaphysics or philosophical theology which purports
to ground the knowledge of all things in “truths” pro-
vided by Sacred Doctrine.

The representatives of Renaissance universality
entertained no such systematic, metaphysical aim, nor
was their learning encyclopaedic. The defining charac-
teristic of their thought is not its generality, but rather
(as Burckhardt saw and Cassirer demonstrated) its
union of experience and reason, of practice and theory.
This basic feature is manifest in the many-sided nature
of the Renaissance man, as it is in the practical and
positive cast of his knowledge. The Schoolman's life
was purely contemplative and academic; the mode of
life of the Renaissance man includes practice of the
arts or crafts or some form of public involvement. The
Schoolman belonged to a religious order; the Renais-
sance man belongs to the lay world (even when, as
in the case of Alberti, he has taken Holy Orders). The
urban society of the time, not the cloister or the uni-
versity, fostered his development and supported him.

This social fact is basic to the revival and ready
acceptance of the humanistic ideal of encyklios paideia.
What made the educational ideas of antiquity vital
once more was their responsiveness to the needs of
Italian society, particularly those of its dominant class,
the urban patriciate. One such feature of classical
paideia was its public-spirited ethos stemming from the
Greco-Roman conviction that man, the complete man,
is a political animal. In fifteenth-century Florence, this
principle served both to elevate bourgeois life, and to
reconcile intellectuals to public and political concerns.
Moreover, the humanists found in the literary or
rhetorical learning of antiquity an educational ideal
that met the cultural aspirations of their society while
satisfying its practical needs. Humanistic learning
enhanced the dignity of despots, of the urban pa-
triciate, and of the humanists themselves by making
classical culture a sign of nobilitas, a nobility more
rational (and hence a matter of virtù) than that of the
old landed aristocracy which was an accident of birth,
of fortuna. It provided a general preparation for the
variety of practical and public positions that had to
be filled. And because the state of social and techno-
logical development reached by the Italian states in
the fifteenth century was comparable to that of classi-
cal civilization, Renaissance society could indeed profit
from knowledge of its political and practical arts.

The esteem won by the manual and practical arts
(such as painting and surveying) is also an index of their
usefulness to the ruling class of the Italian states. They,
too, enhanced the dignity of princes and patriciate and
they furthered their very real interests of wealth and
power. The methodical and practical spirit of Renais-
sance urban life is stamped upon the scientific achieve-
ments of the artistic-technical current of thought,
products of applied mathematics in almost every case:
cryptography, survey maps and scaled nautical charts,
machines and mechanical principles. In this cultural
domain, as in that of humanism, the kind of problems
considered and the way those problems were handled
depended in many ways upon the practical needs of
Italian society and the level of institutional and techni-
cal development it had achieved.

Both types of the Renaissance universal man, the
humanist and artist-scientist, grew out of the orderly,
practical, and confident urban world of fourteenth- and


fifteenth-century Italy, and when the bourgeois basis
of that civilization collapsed, both they and the culture
they bore were overcome by hostile social forces. Three
major stages of social change were distinguished by
Alfred von Martin in the first sociological study of
Renaissance culture as a whole, Soziologie der Renais-
(1932). It is useful to consider these stages here,
especially since the art historian, Arnold Hauser, has
already shown how the three periods of Renaissance
art to which Alberti, Leonardo, and Michelangelo
belong correspond to and reflect certain social features
of the “heroic age of capitalism,” the classical “age
of the rentier” which succeeded it (at least in Florence)
toward the end of the fifteenth century, and the courtly
society of sixteenth-century Italy dominated by Spain
and the Counter-Reformation Church. Many of the
features that characterize them as universal men have
their source in this changing social context, too.

Alberti belongs to the expansive and public-spirited
life of the first period whereas Leonardo belongs to
the second, when Florence yielded to the princely rule
of Lorenzo de' Medici and its culture came to be
shaped by Neo-Platonic ideas, and he lived well into
the time of the invasions that followed on the heels
of Lorenzo's death. Leonardo sank no roots in Medici
Florence (or in Medici Rome), nor did the republican
tradition and civic outlook of Florentine humanism
touch a vital chord in him. His patrons were great
princes and condottieri, and finally the King of France;
and as he passed from the service of one to the other,
he remained peculiarly detached from political events
and factions, peculiarly neutral. He served equally well
both the brutal and ruthless Cesare Borgia and the
Florentine Republic under Piero Soderini. When
Ludovico Sforza met his sorry fate after having been
Leonardo's patron at Milan from 1481 until 1499,
Leonardo redirected many of the ideas he had devel-
oped for a Sforza equestrian monument toward a mon-
ument for the very condottiere who defeated Ludovico
at the behest of the King of France.

This detachment from political and moral issues in
matters of patronage also marks Leonardo's view of
knowledge. Alberti, who never engaged in military
engineering, could still bind his technical-scientific
endeavors to his humanistic ethic, seeing that they
served in fact some constructive social purpose. No
such optimistic outlook was possible for Leonardo who
advertised himself to Ludovico Sforza as a master of
artillery, fortifications, and the advanced weaponry of
the day. Yet for all the violent and destructive ends
to which his science was immediately put, Leonardo
adopted toward it a Faustian attitude of limitless ex-
pansion. The pursuit of physical knowledge which was
checked and directed by ethical considerations in
Alberti became for Leonardo an autonomous intellec-
tual endeavor: “The acquisition of any knowledge
whatsoever is always useful to the intellect, because
it will be able to banish the useless things and retain
those which are good. For nothing can be either loved
or hated unless it is first known” (Notebooks..., ed.
MacCurdy, p. 95). Like Machiavelli, who was very
much his counterpart, Leonardo sounds the keynote
of the modern European ethos of ethically-indifferent
scientific inquiry.

In Leonardo we see most clearly the separation of
humanism and the artistic-technical current of thought
as their distinctive methods were clarified and as the
civic ethic, which bound the two for Alberti, dissolved.
By the time Castiglione's Courtier (Il cortigiano) was
published in 1528, the humanistic ideal of the complete
man had shaken off its republican, bourgeois origins
to attach itself to the courtly principles which were
to dominate Italy and Europe in the succeeding age,
and science and technology, severed from social con-
siderations, began their autonomous career. The ra-
tional spirit of Renaissance civilization survived in the
literary-historical and empirical-mathematical sciences
it founded, but its once integral conception of man
and the world had begun to pull apart. Then, in the
following decades of the sixteenth century, as the
combined forces of Spanish-Imperial arms and the
Counter-Reformation Church dealt the death blow to
the social institutions of Renaissance Italy, the classical
culture which those institutions supported was utterly
transformed. Michelangelo confronts us with a totally
different outlook. Hailed by his contemporary Vasari
as “the perfect exemplar in life, work, and behavior,”
the “divine” Michelangelo renounced the rational
principles fundamental to Renaissance universality.

Painter, sculptor, architect, and poet, Michelangelo
drew little from and contributed less to the two posi-
tive currents of Renaissance thought. His literary in-
terests were centered in Dante and the Bible, not
classical antiquity; and his moral, aesthetic, and
cosmological conceptions were nourished by
Savonarola and Florentine Neo-Platonism, not by
humanism and the empirical-mathematical mode of
thought. Michelangelo's genius, which felt constrained
by man and matter, produced its gigantic works in
isolation and out of an inner wrestling of the soul with
its personal angels and demons. The public life of the
Renaissance had been destroyed: “I keep to myself,”
he wrote to his nephew in 1548, in response to his
warning not to associate in Rome with Florentines who
had been banished from their (and his) native city. “I
go about little, and I speak to nobody—least of all to
Florentines. If a man salute me in the street I cannot
do otherwise than answer him with fair words: then


I pass on. If I could know which of them were exiles
I would pass by with no reply whatever...”
(Michelangelo, ed. Carden, p. 232). To this witness of
the cataclysmic changes of the sixteenth century—an
age in which Rome was sacked by Imperial armies
(1527), Florence besieged and her republic subverted
for all time by the Medici and by Imperial forces
(1529-30), and Italy subject to direct or indirect
Spanish rule—the order of the world had again become
incomprehensible and providential. Neither humanism
nor science entered the circle of Michelangelo's inter-
ests. Art was his society and his world, and the Maker
himself had become his patron: “... there are many
who believe—myself among them—that it was God
who laid this charge [the construction of St. Peter's]
upon me” (ibid., p. 308).

It was Michelangelo who first detached art from the
scientific preoccupations of the classical period. In
Michelangelo the moral life came to be conceived in
theological terms once again. Impelled by a religious
longing for release and regeneration, this late embodi-
ment of the Renaissance universal man unloosed the
human spirit from its rational bonds to physical and
social experience, and in so doing brought about the
final dissolution of the Renaissance view of man and
the world.

Art, science, and literary humanism henceforth
pursued their own independent careers. The cohesion
of Renaissance universality was gone, and it was not
to be restored any more than were the peculiar social
conditions which had once favored its rise. But the
ideal of a rational unification of knowledge persisted;
it passed from humanism and empirical-mathematical
thought, which did not of themselves issue in a system-
atic ordering of knowledge, to philosophy which did.
Renaissance universality holds a logical, as well as a
chronological, place between the theological syntheses
of medieval learning and the modern philosophical
syntheses of rational knowledge. Neither the studia
nor the sciences of measurement could
embrace the entire globus intellectualis, since neither
is a system of philosophy; but they both prepared the
way for the modern unifications of learning which,
from the time of Francis Bacon and René Descartes,
have regarded as “knowledge” only that which is
grounded in experience and reason. The achievement
of Renaissance thought is positive knowledge, the dual
tradition of the cultural and the empirical-math-
ematical sciences. And it is this scientific tradition
which has provided the cumulatively changing con-
tents for the modern syntheses of knowledge from
Francis Bacon to the Encyclopédie of Diderot and
d'Alembert, from Leibniz to the twentieth-century
philosophy of culture of Ernst Cassirer.