THE COGNITIVE STYLE OF POWERPOINT

Edward R. Tufte Graphics press LLC, 2003, 27 pp.   ISBN 0-9613921-5-0
www.edwardtufte.com

Edward Tufte is a former professor of statistics and analytical design at
Yale.  He writes, designs and publishes his own books on analytical design.
This essay is a scathing critique of PowerPoint.  "Some methods of
presentation are better than others.  And PowerPoint is rarely a good
method." (26)  Using farcical slides as well as real-life examples, he
illustrates how PowerPoint weakens presentations of scientific data, risk
assessment, and strategic planning.

Slides often reduce the analytical quality of presentations.  The ready-made
designs usually weaken verbal and spatial reasoning and almost always
corrupt statistical analysis. (3)

"PowerPoint is entirely presenter-oriented, and not content-oriented, not
audience-oriented."  The cognitive style of standard default templates is
faulty.  It results in "foreshortening evidence and thought, low spatial
resolution, a deeply hierarchical single path structure as the model for
organizing every type of content, breaking up narrative and data into slides
and minimal fragments, rapid temporal sequencing of thin information rather
than focused spatial analysis, conspicuous decoration and Phluff, a
preoccupation with format not content, an attitude of commercialism that
turns everything into a sales pitch." (4)

"Many true statements are too long to fit on a PP slide, but this does not
mean we should abbreviate the truth to make the words fit.  It means we
should find a better way to make presentations." (4)  A slide says
"Correlation is not causation."  This is misleading in that while
correlation does not prove causation, it is a necessary condition and a good
hint.

Bullet lists leave critical relationships unspecified.  They communicate
only sequence, priority or membership in a set.  They ignore and conceal the
causal assumptions and analytic structure of the reasoning. Sentences with
subjects and verbs are usually better. (5-6)

Tufte shows three PowerPoint presentations used by NASA officials to report
the in-flight risk assessment of the damage to the ill-fated Challenger. His
critique of the over-optimistic assessment is crushing.  The reports used
standard PP formats with bullet outlines, segregation of words and numbers,
cryptic typography, etc.

The PowerPoint information hierarchy mimicked the hierarchical structure of
the bureaucracy that produced it.  "The choice of headings, arrangement of
information, and size of bullets on the key chart served to highlight what
management already believed."  (10)

"PowerPoint will not do for serious presentations.  Serious problems require
serious tools." (11)

A picture can communicate much more than a thousands words and much more
quickly.  However, "nearly all PowerPoint slides that accompany talks have
much lower rates of information transmission than the talk itself.  Too
often the images are content-free clip art, the statistical graphics don't
show data, and the text is grossly impoverished."  "The PowerPoint slide
typically shows 40 words, which is about 8 seconds-worth of silent reading
material."  (12)

"A vicious circle results.  Thin content leads to boring presentations. To
make them unboring, PPPhluff is added, damaging the content, making the
presentation even more boring...."  For serious presentations replace slides
with handouts showing words, numbers, data graphics and images together.
"Thin visual content prompts suspicions: 'What are they leaving out?  Is
that all they know?  Does the speaker think we're stupid?'  'What are they
hiding?'"  (12)

The metaphor behind the PP cognitive style is the software corporation and
program writing "(deeply hierarchical, nested, highly structured,
relentlessly sequential, one-short-line-at-a-time) and marketing (fast pace,
misdirection, advocacy not analysis, slogan thinking, branding, exaggerated
claims, marketplace ethics)." (13)

A better metaphor for presentations is good teaching, exhibiting the core
ideas of "explanation, reasoning, finding things out, questioning, content,
evidence, credible authority not patronizing authoritarianism...." (13)

The actual text of the Gettysburg Address is set next to six hilarious
PowerPoint slides representing it.  My favorite is the chart showing in two
columns the number of new nations: -87 years, 1; now, 0.  (You know, "Four
score and seven years ago...")

The use of PowerPoint with medical data and statistical information is
critiqued on pp. 16-21.

"The PP slide format has probably the worst signal/noise ration of any known
method of communication on paper or computer screen." (22)

"Sometimes quick chunks of thin data may be useful (flash-card memorizing),
other times not (comparisons, links, explanations).  But formats,
sequencing, and cognitive approach should be decided by the character of the
content and what is to be explained, not by the limitations of the
presentation technology." (23)

"Presentations largely stand or fall depending on the quality, relevance,
and integrity of the content.  The way to make big improvements in a
presentation is to get better content." (24) [However, we all know that
presentation skills are also very important.  Dlm]

"Audience boredom is usually a content failure, not a decoration failure. At
a minimum, a presentation format should do no harm to content."  (24)

"The practical conclusions are clear.  PowerPoint is a competent slide
manager and projector for low-resolution materials.  And that's about it."
(24)

"Never use PP templates for arraying words or numbers.  Avoid elaborate
hierarchies of bullet lists.  Never read aloud from slides.  Never use PP
templates to format paper reports or web screens.  Use PP as a projector for
showing low-resolution color images, graphics, and videos that cannot be
reproduced as printed handouts at a presentation."  "Thoughtfully planned
handouts at your talk tell the audience that you are serious and precise;
that you seek to leave traces and have consequences.  And that you respect
your audience." (24)

"PP has a distinctive, definite, well-enforced, and widely-practiced
cognitive style that is contrary to serious thinking.  PP actively
facilitates the making of lightweight presentations."  (26)

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________________________ David Mays ACMC http://www.davidmays.org