
shytone
books music
essays
home exploratories
new this month
book
reviews
Edward
R. Tufte: Envisioning
Information
(Graphics Press: 1990)
“The world is
complex, dynamic, multidimensional: the paper is static,
flat. How are we to represent the rich visual world of
experience and measurement on mere flatland? This book
celebrates escape from flatland.... Revealed here are
design strategies for enhancing the dimensionality and
density of portrayals of information - techniques exemplified
in maps, the manuscripts of Galileo, timetables, notation
describing dance movements, aerial photographs, the Vietnam
Veterans Memorial, electrocardiograms, drawings of Calder
and Klee, computer visualizations, and a textbook of Euclid’s
Geometry. Our investigation yield general principles that
have specific visual consequences, governing the design,
editing, analysis, and critique of data representations.
These principles help to identify and explain design excellence
- why some displays are better than others. Charts, diagrams,
graphs, tables, guides, instructions, directories, and
maps comprise an enormous accumulation of material. Once
described by Philip Morrison as ‘cognitive art’,
it embodies tens of trillions of images created and multiplied
the world over, every year. Despite the beauty and utility
of the best work, design of information has engaged little
critical or aesthetic notice: there is no Museum of Cognitive
Art. This book could serve as a partial catalogue for
such a collection.... To envision information - and what
bright and splendid visions can result - is to work at
the intersection of image, word, number, art. The instruments
are those of writing and typography, of managing large
data sets and statistical analysis, of line and layout
and color. And the standards of quality are those derived
from visual principles that tell us how to put the right
mark in the right place.... [These] principles of information
design are universal - like mathematics - and are not
tied to unique features of a particular language or culture.
Consequently, our examples are widely distributed in space
and time: illustrations come from 17 countries and 7 centuries,
and, for that matter, 3 planets and one star.”
(Tufte, pp.9-10.)
Visual intelligence, even today, amidst the new wealth
of visualizations opened up by the wide spread of modern
computing power, is a sadly neglected area among non-specialists.
Yet, more and more we are coming to depend on same, in
an increasing number of areas. To my mind, the best (and
by far the most seductive) introduction to this realm
is undoubtedly to be found in the work of Edward R. Tufte...and,
particularly in this, the central volume in his landmark
trilogy upon visual information...
Now, that may sound surpassingly dry to most... Well,
if so, then you can think again, because I’m here
to tell you now that this is, almost certainly, the loveliest
book I own...beautifully written, laid-out, and printed
- and, filled with startlingly shapely graphics and images,
which also happen to serve practical ends...like most
human art, contra ideology. Tufte’s is truly a name
to conjure with amongst those who labour in the cognitive
arts - his analyses now supply the gold standard for any
discussion of excellence in this area - but, it is criminally
little-known in lay circles, despite the fact that this
book would beautifully grace anyone’s coffee table.
Unfortunately, restricted as I am here to text, I can
only assert - rather than show you - the quality of illustration
in this review. However, with words & ideas I, as
usual, can be most generous. The rest, however, must (hopefully)
await your introduction to the book itself...
“Nearly every
escape from flatland demands extensive compromise, trading
off one virtue against another; the literature consists
of partial, arbitrary, and particularistic solutions;
and neither clever idiosyncratic nor conventionally adopted
designs solve the inherent general difficulties of dimensional
compression. Even our language, like our paper often lacks
immediate capacity to to communicate a sense of dimensional
complexity.... [And] exactly the same design strategies
are found, again and again, in the work of those faced
with a flood of data and images, as they scramble to reveal,
within the cramped limits of flatland, their detailed
and complex information. These design strategies are surprisingly
widespread, albeit little appreciated, and occur quite
independently of the content of the data.”
(Tufte, pp.15-23)
“Too many data
presentations, alas, seek to attract and divert attention
by means of display apparatus and ornament.... Lurking
behind chartjunk is contempt both for information and
the audience. Chartjunk promoters imagine that numbers
are boring, dull, and tedious, requiring ornament to enliven.
Cosmetic decoration, which frequently distorts the data,
will never salvage an underlying lack of content. If the
numbers are boring, then you’ve got the wrong numbers....
Worse is contempt for our audience, designing as if readers
were obtuse and uncaring. In fact, consumers of graphics
are often more intelligent about the information at hand
than those who fabricate the data decoration. And, no
matter what, the operating moral
premise of information design should be that our readers
are alert and caring; they may be busy, eager to get on
with it, but they are not stupid. Clarity and simplicity
are completely opposite simple-mindedness.... Standards
of excellence for information design are set by high
quality maps, with diverse
bountiful detail, several layers of close reading combined
with an overview, and rigorous data from engineering surveys.
In contrast, the usual chartjunk performances look more
like posters than maps. Posters are meant for viewing
from a distance, with their strong images, large type,
and thin data densities. Thus poster design provides very
little counsel for making diagrams that are read more
intensely.... Excellence in presenting information requires
mastering the craft, and spurning the ideology.”
(Tufte, pp.33-5)
One of the great joys of this book is that it offers us
the rare spectacle of tough-minded and clear talk about
aesthetic standards (as morality, what’s more),
with absolutely no
sign of either high-cultural snobbery, or abasement before
relativistic idols. The reason for this is simple: in
a field where practitioners still totally dominate criticism,
and where the functional dimension of quality may be tested
by relatively simple means (should people be interested
in doing so), the disfigurements of “Theory”
have comparatively little purchase, albeit fashions may
still obscure matters...
Nonetheless, issues of art, craft, and science can, still,
easily find their (naturally complementary) footing when
dealt with by an analytic generalist/craftsman such as
Tufte, to the benefit of all... And, if you thought his
initial statements promised more rigour than anyone could
deliver on qualitative issues, then think again. Because
it’s exactly in the details where his work makes
its strongest points, as in this evocation of the richness
we can bring to visual information:
“Micro/macro designs...[can
usefully deliver] large quantities of data at high densities,
up to thousands of bits per square centimeter, and 20
million bits per page, pushing the limits of printing
technology. Such quantities are thoroughly familiar, although
hardly noticed: the human eye registers 150 million bits,
the 35 mm slide some 25 million bits, conventional large-scale
topographic maps up to some 150 million bits, the color
screen of a small personal computer 8 million bits....
We thrive in [such] information-thick worlds because of
our marvellous and everyday capacities to select, edit,
single out, structure, highlight, group, pair, merge,
harmonize, synthesize, focus, organize, condense, reduce,
boil down, choose, categorize, catalog, classify, list,
abstract, scan, look into, idealize, isolate, discriminate,
distinguish, screen, pigeonhole, pick over, sort, integrate,
blend, inspect, filter, lump, skip, smooth, chunk, average,
approximate, cluster, aggregate, outline, summarize, itemize,
review, dip into, flip through, browse, glance into, leaf
through, skim, refine, enumerate, glean, synopsize, winnow
the wheat from the chaff, and separate the sheep from
the goats.”
(Tufte, pp.49-50)
“Fine texture
of exquisite detail leads to personal micro-readings,
individual stories about the data.... Detail cumulates
into larger coherent structures...[and, therefore] simplicity
of reading derives from the context of detailed and complex
information, properly arranged. A most unconventional
design strategy is revealed: to clarify, add detail ....
At work is a critical and effective principle of information
design. Panorama, vista, and prospect deliver to viewers
the freedom of choice that derives from an overview, a
capacity to compare and sort through detail. And that
micro-information, like smaller texture in landscape perception,
provides a credible refuge where the pace of visualization
is condensed, slowed, and personalized. These visual experiences
are universal, rooted in human information-processing
capacities and in the abundance and intricacy of everyday
perceptions. Thus, the power of micro/macro designs holds
for every type of data display, as well as for topographic
views and landscape panoramas. Such designs can report
immense detail, organizing complexity through multiple
and (often) hierarchical layers of contextual reading.”
(Tufte, pp.37-8)
And, should you have been misled by modernist aesthetic
ideologies into overvaluing simplicity, Tufte (with some
help from Josef Albers and psychological researchers)
can set you right with ease for, as I said, the functional
dimension of such artwork is eminently testable...and
the results rather different from what we have been led
to expect...
“Visual
displays rich with data are not only an appropriate
and proper complement to human capabilities, but also
such designs are frequently optimal. If the visual task
is contrast, comparison and choice - as so often it
is - then the more relevant information within eyespan,
the better. Vacant, low-density displays, the dreaded
posterization of data spread over pages and pages, require
viewers to rely on visual memory - a weak skill....
Micro/macro designs enforce both local and global comparisons
and, at the same time, avoid the disruption of data
switching...[and] allow viewers to select, to narrate,
to recast and personalize data for their own use. Thus
control of information is given over to viewers, not
to editors, designers or decorators.... Now and then,
it is claimed that vacant space is ‘friendly’
(anthropomorphizing an inherently murky idea) but it
is not how much empty space there is, but rather how
it is used. It is not how much information there is,
but rather how effectively it is arranged.
Showing complexity is hard work. Detailed micro/macro
designs are difficult to produce, imposing substantial
costs...similar to that of first-class cartography (which,
in the main, can be financed only by governments). The
conventional economies of declining costs for every
additional bit will usually be offset by a proliferation
of elaborate complexities provoked by interacting graphical
elements. Still, a single high-density page can replace
twenty scattered posterizations, with possible savings
when total expenses are assessed.... [And,] what about
confusing clutter? Information overload? Doesn’t
data have to be ‘boiled down’ and ‘simplified’?
These common questions miss the point, for the quantity
of detail is an issue completely separate from the difficulty
of reading. Clutter and confusion are failures
of design, not attributes of information.
Often the less complex and less subtle the line, the
more ambiguous and less interesting is the reading.”
(Tufte, pp.50-1)
“The concept that
‘the simpler the form of a letter the simpler its
reading’ was an obsession of beginning constructivism.
It became something like a dogma, and is still followed
by ‘modernistic’ typographers. This notion
has proved to be wrong, because in reading we do not read
letters but words, words as a whole.... [whilst] ophthalmology
has disclosed that the more the letters are differentiated
from each other, the easier is the reading...[so] when
comparing serif letters with san-serif, the latter provide
an uneasy reading. The fashionable preference for san-serif
in text shows neither historical nor practical competence.”
(Josef Albers, quoted
in Tufte, p.51)
“So much for the
conventional, facile, and false equation: simpleness of
data and design = clarity of reading. Simpleness is another
aesthetic preference, not an information display strategy,
not a guide to clarity. What we seek, instead, is a rich
texture of data, a comparative context, an understanding
of complexity revealed with an economy of means.... But,
finally, the deepest reason for displays that portray
complexity and intricacy is that the worlds we seek to
understand are complex and intricate.”
(Tufte, p.51)
While each chapter in this book has its own centre of
gravity - typically a basic approach to the display of
information - the argument is more recursive, returning
again and again to the perceptual biases of viewers, the
necessity for trade-offs between conflicting ideals, and
the omnipresence of the interaction effects which mean
that honing such displays can never be reduced to a simple
formula:
“Among the most
powerful devices for reducing noise and enriching the
content of displays is the technique of layering and separation,
visually stratifying various aspects of the data. Effective
layering of information is very difficult; for every excellent
performance, a hundred clunky spectacles arise. An omnipresent,
yet subtle, design issue is involved: the various elements
collected together on flatland interact ,
creating non-informational patterns and texture simply
through their combined presence. Josef Albers described
this visual effect as 1+1 = 3 or more ,
when two elements show themselves along with assorted
incidental by-products of their partnership - occasionally
a basis for pleasing aesthetic effects, but always a continuing
danger to data exhibits. Such patterns become dynamically
obtrusive when our displays leave the relative constancy
of paper and move to the changing video flatland of computer
terminals. There, all sorts of unplanned and lushly cluttered
interacting combinations turn up, with changing layers
of information arrayed in miscellaneous windows surrounded
by a frame of system commands and other computer administrative
debris.... What matters - inevitably, unrelentingly -
is theproper relationship
among information layers. These visual relationships must
be in relevant proportion and in harmony to the substance
of the ideas, evidence, and data conveyed. ‘Proportion
and harmony’ need not be vague counsel; their meanings
are revealed in the practice of detailed visual editing
of data displays.”
(Tufte, pp.53-4)
“Layering of data,
often achieved by the felicitous subtraction of weight,
enhances representation of both data dimensionality and
density on flatland. Usually, this involves creating a
hierarchy of visual effects, possibly matching an ordering
of information content. Small, modest design moves can
yield decisive visual results, as in the...intriguing
demonstrations of the illusory borders of subjective contours....
The noise of 1+1 = 3 is directly proportional to the contrast
in value (light/dark) between figure and ground. On white
backgrounds, therefore, a varying range of lighter colors
will minimize incidental clutter.... These are not trivial
cosmetic matters, for signal enhancement through noise
reduction can reduce viewer fatigue as well as improve
accuracy of readings.... Clarity is not everything, but
there is little without it.... Information consists of
differences that make a difference.”
(Tufte, pp.60-5)
Perhaps Tufte’s favourite strategy, at least to
judge by the (self-designed) cover of his book, is that
of the small multiple...which creates an array of easily
comparable images. This is because, clearly, such a display
insistently draws us to comparison and - as long as the
structure is simple to decode - will reliably deliver
no matter how innumerate (or nonanalytical) the audience.
And besides, they do
have an aesthetic charm all their own...
“[One key form
of display] is the small multiple, with the same design
structure repeated for all the images. An economy of perception
results; once viewers decode and comprehend the design
for one slice of data, they have familiar access to data
in all the other slices. As our eye moves from one image
to the next, this constancy of design allows viewers to
focus on changes in information rather than changes in
graphical composition. A steady canvas makes for a clearer
picture.... Small multiples work as efficient and convincing
summaries of data or an argument, making the same point
again and again by offering complementary variations on
the major substantive theme.... Such displays are likely
to be especially persuasive and memorable in situations
where most information consists of spoken words - as in
a trial. Courtroom graphics can overcome the linear, nonreversible,
one-dimensional sequencing of talk talk talk, allowing
members of a jury to reason about an array of data at
their own pace and in their own manner. Visual displays
of information encourage a diversity of individual viewer
styles and rates of editing, personalizing, reasoning,
and understanding. Unlike speech, visual displays are
simultaneously a wideband and a perceiver-controllable
channel.... Small multiples whether tabular or pictorial,
move to the heart of visual reasoning - to see, distinguish,
choose.... Their multiplied smallness enforces local comparisons
within our eyespan, relying on the active eye to select
and make contrasts rather than on bygone memories of images
scattered over pages and pages.”
(Tufte, pp.29-33)
By the time we have arrived at colour, Tufte has impressed
upon us just how difficult it is to balance the conflicting
demands made by the design of information display...but,
once there, it is clear that colour makes some of the
toughest demands of all. Nonetheless, as always, Tufte
shows us exactly what the best strategies are, just why
(in psychological terms) we deal better with these than
their (often fashionable) rivals, and tops this off with
cautionary insights into the design process of the kind
that non-practitioners can rarely deliver...
“In representing
and communicating information, how are we to benefit from
color’s great dominion? Human eyes are exquisitely
sensitive to color variations: a trained colorist can
distinguish amongst 1,000,000 colors, at least when tested
under contrived conditions of pairwise comparison....
For encoding abstract information, however, more than
20 or 30 colors frequently produce not diminishing but
negative returns. Tying color to information is as elementary
and straightforward as color technique in art, ‘To
paint well is simply this: to put the right color in the
right place,’ in Paul Klee’s ironic prescription.
The often scant benefits derived from coloring data indicate
that even putting a good color in a good place is a complex
matter. Indeed, so difficult and subtle that avoiding
catastrophe becomes the first principle in bringing color
to information: Above all, do no harm.”
(Tufte, p.81)
“First
rule: Pure, bright,
or very strong colors have loud, unbearable effects when
they stand unrelieved over large areas adjacent to each
other, but extraordinary effects can be achieved when
they are used sparingly on or between dull background
tones... The organization of the earth’s surface
facilitates graphic solutions of this type in maps. Extremes
of any type - such as highest land zones and deepest sea
troughs, temperature maxima and minima - generally enclose
small areas only. If one limits strong, heavy, rich, and
solid colors to the small areas of the extremes, then
expressive and beautiful patterns occur...”
(Eduard Imhof, quoted
in Tufte, p.82)
Cautionary notes sounded, Tufte then goes on to analyse
the fundamentals of colour use - note the implicit hierarchy
involved in his list, which also makes for an interesting
way of viewing color use in the natural world, not to
mention other forms of (non-cognitive?) art...
“The fundamental
uses of color in information design [are] to label
(color as noun), to
measure (color as quantity),
to represent or imitate reality
(color as representation), and to enliven or decorate
(color as beauty).”
(Tufte, p.81)
“What palette
of colors should we choose to represent and illuminate
information? A grand strategy is to use colors
found in nature , especially
those on the lighter side, such as blues, yellows, and
grays of sky and shadow. Nature’s colors are familiar
and coherent, possessing a widely accepted harmony to
the human eye - and their source has a certain definite
authority. A palette of nature’s colors helps suppress
production of garish and content-empty colorjunk. Local
emphasis for data is then given by means of spot highlights
of strong color woven through the serene background.”
(Tufte, p.90)
“Any color coding
of quantity (whether based on variations in hue, value,
or saturation) is potentially sensitive to interactive
contextual effects. These perceived color shifts, while
an infrequent threat to accuracy of reading in day-to-day
information design, are surprising and vivid - suggesting
that color differences should not be relied upon as the
sole method for sending a message amidst a mosaic of complex
and variable data.... Color itself is subtle and exacting.
And, furthermore, the process of translating perceived
color marks on paper into quantitative data residing in
the viewer’s mind is beset by uncertainties and
complexities. These translations are nonlinear (thus gamma
curves), often noisy and idiosyncratic, with plenty of
differences in perception found among viewers (including
several percent who are color-deficient). Multiple signals
will help escape from the swamp of perceptual shifts and
other ambiguities in reading. Redundant and partially
overlapping methods of data representation can yield a
sturdy design, responding in one way or another to potential
visual complications - with, however, a resulting danger
of fussy, cluttered, insecure, committee-style design.
A crystalline, lucid redundancy will do. Transparent and
effective deployment of redundant signals requires, first,
the need - an
ambiguity or confusion in seeing a data display that can
in fact be diminished by multiplicity - and, second, the
appropriate choice of design technique
(from among all the various methods of signal reinforcement)
that will work to minimize the ambiguity of reading. Disregard
of these conspicuous distinctions will propagate a gratuitous
multiplicity.”
(Tufte, pp.92-4)
Of the trilogy of which this forms the second volume,
Tufte has stated that the first is about number, the second
about nouns, and the third about verbs...albeit I would
argue there is considerable overlap, particularly in this
central volume. And, whilst number is frequent here, scattered
throughout the examples, he mostly saves the “verbs”
in this one for the final chapter, a preliminary exploration
of the narrative lodes to be mined in the third volume,
Visual Explanations.
Here, while the argument is more tentative, he expresses
most clearly the aesthetic lesson of his work...a lesson
all Humanists should truly take to heart, rather than
continuing to rehearse the prejudices of our training:
“Systems of dance
notation translate human movements into signs transcribed
into flatland, permanently preserving the visual instant.
Design strategies for recording dance movements encompass
many of the usual (nearly universal, nearly invisible)
display techniques: small multiples, close text-figure
integration, parallel sequences, details and panorama,
a polyphony of layering and separation, data compression
into content-focused dimensions, and avoidance of redundancy.
Now and again, the paper encoding reflects the refinement
of the dance itself - a flowing and graceful line embellished
by disciplined gesture, a dynamic symmetry inherent to
both individual and group proceedings. Moreover, some
notation systems engender a visual elegance all their
own, independently of the motions described. Our understanding
of the aesthetics of information is enriched by examining
dance narratives and their visual texture. We come to
appreciate how the underlying designs bring about and
enable the joy growing from the comprehension of complexity,
from finding pattern and form amidst commotion.”
(Tufte, pp.114-15)
Edward R. Tufte’s Envisioning
Information is a genuinely gorgeous book, as befits
its status as a groundbreaking exploration of types of
art too often taken for granted. Yet, as the quotations
above - unceremoniously stripped of their visuals - show
so clearly, it is also a beautifully-written book, in
which the art, craft and science of this area are all
accorded their proper due by Tufte, whilst nonsense is
treated as rudely as it deserves...something all too rare
in explorations of aesthetic terrain. Moreover, precisely
because the art he examines has a purpose apart from the
aesthetic - as, in fact, has most art over the span of
human history - it is much
simpler to separate the wheat from the chaff here, thus
providing us one clear route, at least, into the troubled
terrain of the aesthetic.
And, it is not only the aesthetic that Tufte provides
us w/a route into... In an era when the Humanities is
almost totally dominated by overly language-centric models,
Tufte’s work clearly shows us just how (and why)
we think visually - and, by exploring how designers can
best aid us in that, through copious (and beautiful examples)
- he teaches us to properly comprehend this neglected
dimension of our understandings...a crucial lesson for
even those who will never attempt visual design themselves,
although that, today, is a shrinking group indeed. In
its uncompromisingly high production standards, too, this
book offers us, in toto, a genuine vision of something
to aspire to...in an age when excellence is, sadly, all-too-readily
confused w/elitisms of varying sorts. For, in all these
ways, and for all of these reasons, this is truly a book
to treasure...
“We envision information
in order to reason about, communicate, document, and preserve
that knowledge - nearly always carried out on two-dimensional
paper and computer screen. Escaping this flatland and
enriching the density of data displays are the essential
tasks of information design. Such escapes grow more difficult
as ties of data to our familiar three-space world weaken
(with more abstract measures) and as the number of dimensions
increases (with more complex data). Still, all the history
of information displays and statistical graphics - indeed
of any communication device - is entirely a progress of
methods for enhancing density, complexity, dimensionality,
and even sometimes beauty. Some of these methods, identified
and described on the chapters that follow, include micro/macro
readings of detail and panorama, layering and separation
of data, multiplying of images, color, and narratives
of space and time. By giving the focus over to data rather
than data containers, these design strategies are transparent
and self-effacing in character. Designs so good they are
invisible.”
(Tufte, p.33)
John
Henry Calvinist
|
|