The Trouble with PowerPoint 🧑‍🏫

Summarizing Edward Tufte's essay "The Cognitive Style of PowerPoint".

It weakens verbal and spatial reasoning and corrupt statistical analysis.

PP is presenter-oriented and not content-oriented or audience-oriented.

PP style: short on evidence and thought, hierarchical single path structure, breaking up narrative into slides, preoccupation with format not content and the feeling that everything is a sales pitch.

His first point about low resolution compared to 35mm slides is no longer relevant as screens approach 4k resolution.

Low amount of information in built in statistical figures is also not relevant, because if needed, I'll use external graphics and plots, not use the built it tools for that, but a good point nevertheless.

Next is the bullet-point language: it makes us lazy and stupid; they leave out important relationships between the topics; they can only show one out of these 3: sequence, priority or membership. They hide the causal and analytic structure of reasoning. More often than not, sentences with subjects and verbs are better.

Mentioning the Columbia shuttle accident and how PP presentations were part of the fault by miscommunicating the potential damage to the wing and the dangers. They give examples: a slide with 6 hierarchical levels, a slide with a dense table where you can't read the data. PP slides were used instead of technical papers as a method of technical communication.

Complicated topics don't really require hierarchical bullets outline, think about physics books.

Next we go to data transmission rate. 100-160 words per minute is not a high resolution transmission. People can receive much higher rates using an image or a video. However slides have much lower rates than the actual talk itself. Typical PP slide has 40 words which is about 8 seconds of silent reading. Here I thought that it's not recommended putting a lot of text into a single slide. One solution is giving handouts with the words, numbers, data, graphics. We shouldn't confuse the two issues of "amount of details" and "difficulty of understanding". Sometimes the more intense the details the greater the clarity (not sure I agree with that).

He's making a point on the metaphor for presenting; instead of a leader making power points he's suggesting good teaching. However many ideas of teaching - explanation, reasoning, questioning, evidence, not patronizing - are contrary to the hierarchical market-pitch bullet-point approach. It should be worrisome that school children learn to use PP slides instead of writing reports. Looking at elementary school PP slides, you see 10-20 words, 3-6 slides which means 80 words or 15 seconds of reading.

Templates only enforce the limitations of PP.

Tables are good example; mean number of numbers is 12. Tables are meant for comparison, # of comparison scales quadratically with cells, dividing into smaller tables lead to less data analysis.

The problem continues when PP slides are printed as part of a report, an email or presented in web pages. Printed PP slides are a waste of paper. PP slides are much lower information density than news websites, not to mention non fiction books. It's time people presenting address the audience as serious people.

I always think to myself that I can't create a PDF of my presentation and send it to people because it's so lacking in information and context and can't be understood without my physical presentation. Well, now I know why and that it shouldn't be the case, i.e. the presentation should have enough material and context by itself.

Transitions and line-by-line revealing are terrible. Handouts is one way the audience can control the flow of information for themselves. Another way is showing multiple slides at the same time; it enables us to reason about multiple pieces of information.

Mentions George Miller's classic 1956 paper "The Magical Number Seven, Plus or Minus Two." About the ability of people to remember 7 pieces of nonsense information at a given time. It doesn't say anything about amount of related pieces of data.

So what should we do? Presentation depend on the quality of the content. The format won't salvage the content. Boredom has to do with content not a styling issue. He really believes that handouts should replace PP because they can show data, tables, images far better than PP slides and match transfer rates with other formats. He suggests a sheet of paper folded in 2 creating 4 pages of content.

It's a game: people pretend to give a talk and the audience pretend to listen and learn. Why are we having this meeting? Should be the main question.

A few extra points made by commenters on his essay:

Why blame PP, it's just a tool: PP enforces a cognitive style that is opposing serious thinking. The evidence of the essay suggests there is a defect in PP. The alternative that PP uses are lightweight while others are not is not correct, as the NASA case shows.

What can I do if PP is expected at my workplace: use handouts and use PP for some images and talk about the handouts. No need to attract attention to the presentation method.

I found it extremely interesting. I give a couple of presentations a year. My understanding of what considered good practice is the exact opposite of what Tufte is advocating. I recognize all the faults he mentions: sales-pitch attitude, reduction of complexity, low data-rate transfer, printed presentation can't stand by itself but I thought it was "by design", i.e. the slides serve as a graphical companion to my physical presentation which comprised of the things I say and do on stage. I'm not sure he's advocating to have *all* the information in the presentation or just that the presentation slides are a poor tool. I think the handouts he's suggesting also don't tell 100% of the story by themselves. Anyways, it's going to be hard to fight the habit of creating simple slides, not a lot of text, short sentences, stemming from the need to fight for attention against the data on the slides, but maybe I'm thinking about this all wrong.

Let me know if you found it useful or have some thoughts of your own.