The power of diagrams


The creation of diagrams often seems to be an after-thought for many non-fiction writers, something to be fitted in quickly once the serious job of writing has been completed. And sadly, there are other writers who are happy to produce long books without any diagrams at all.

However I believe that diagrams are both:

a) critical in the writing of any non-fiction book because sometimes it’s only after creating a diagram of how the different parts of a book fit together that gaps in the logic of the argument or the content become apparent and

b) critical in helping readers understand the contents of a book more clearly.

I think there’s also something profoundly uninviting when one picks up a book that just consists of pages and pages of unbroken text without any diagrams or illustrations.


Let’s start with a definition of diagrams.

A diagram can be defined as a visual representation of the relationship between different elements or, to put it another way, as a visual representation of how individual parts relate to the whole.

The key aspect about diagrams is that almost anything can be diagrammed.

As Professor Robbie Nakatsu writes in his book Diagrammatic Reasoning in AI (Wiley-Blackwell, 2009 – p.303):

“almost any type of entity can be modeled”, including “people, things, concepts, events, activities, decision points, sets, actions, steps”.

(See Note 1 for a detailed description of the different ways that elements and relationships can be represented in diagrams.)

It’s also important to realise that diagrams rarely exist on their own.

The summary they provide generally needs to be expanded on with more detailed textual explanation.

Particular aspects of diagrams

I want to discuss four examples of diagrams or series of diagrams I have come across recently that show the explanatory power of diagrams in different ways:

  • Aspect 1: Communicating the big picture 
  • Aspect 2: Communicating the essence of ideas
  • Aspect 3: Communicating complexity
  • Aspect 4: Making processes more tangible.

What I find fascinating is how they all allow the reader to achieve a much deeper understanding of the author’s ideas than would have been possible with just textual descriptions.

And while they focus on particular domains – history, meditation and educational leadership – the way these diagrams are used can be applied much more generally.

Aspect 1: Communicating the big picture

In his book The Shortest History of Europe (Old Street Publishing, 2012) , John Hirst encapsulates in a simple diagram key changes in European ideas and belief over 1,300 years from the fall of the Roman Empire in about 476AD to the Romantic Movement in the 18th and 19th centuries.

In a few seconds one can understand the key points of his argument, which understandably he needs 41 pages of text to explain in detail because of the breadth and complexity of the topics he is addressing.

His argument becomes much more understandable and memorable because of the clarity of his diagram.

For example, Hirst’s explanation below discussing a divide in European culture that remains powerful to this day becomes clearer by also being able to look at the diagram and see the opposing arrows at the bottom along with the three key elements at the top:

“The twin forces of science and progress on the one hand and emotion and liberation on the other are still very strong. Sometimes they can reinforce each other; sometimes they are opposed to each other …

It is our fate to be torn, divided and confused. Other civilisations have a single tradition and not this odd threesome. They are not so liable to the turmoil, overturnings and confusion that we have had in our moral and intellectual life.” (p.43 and 45)

Authors often make it hard for the reader to work out what their overall argument is.

The beauty of diagrams like this one is that the reader has to do less unnecessary work to understand what the author is trying to say.

Aspect 2: Communicating the essence of ideas

James Hawes uses equation and simple sequence diagram formats to communicate the essence of an idea or a description in the second Shortest History series book, The Shortest History of Germany (Old Street Publishing, 2018).

He uses an equation format to show the components of a topic or an outcome.

This is Hawes’s diagram explaining the impact of Hegel’s ideas (p.95).

And this is his diagram describing Bismarck’s dream of a global German-British alliance before Disraeli lost power in 1880.

There are many other topics for which he uses these equation diagrams, including:

  • the component parts of a strategy: Prince Albert’s Coburg Plan
  • the component parts of a power structure: the 2nd German Empire (and modern dictatorships)
  • the reasons behind major outcomes: the end of Prussian hegemony in Germany/Germany’s loss of two wars in the 20th century
  • the elements of an ideology: Nazi ideology.

He also uses a sequence diagram to provide a simple explanation to sum up the financial relationship between western and eastern Germany since 1871.

With complex ideas and descriptions, it is so easy for readers to get overwhelmed by detail.

James Hawes shows how simple diagrams can make it much easier for readers to immediately ‘get’ the key points of an explanation before going on to explore the points in more detail in the text.

(As an aside, I’d recommend both these Shortest History books to anyone interested in the histories of Europe and/or Germany.)

Aspect 3: Communicating complexity

Shinzen Young is an American mindfulness teacher who is committed to explaining his ideas clearly.

The series of diagrams I want to discuss are taken from his paper What is Mindfulness?.

From page 40 to page 45, he describes a series of ten stages that meditators go through as they become more proficient at mindfulness, using an illustration and nine diagrams to amplify his textual description.

The diagrams move in the direction of increasing complexity as meditators develop the capacity to experience images, internal dialogue, and emotional and physical body sensations on an increasingly granular level.

The whole series of diagrams is worth looking at but I am just going to show three here.

State 2 – Got the form

State 5 – Detect underlying wavelets

State 8 – Arising becomes rich

Each of the diagrams has an accompanying textual explanation. To give an example, he describes State 8 with the following text, explaining what the arrows represent and the overall meaning of the diagram:

“The outward directed arrows indicate the pulling apart, the polarizing, of Nothing into expansive and contractive forces.

The inward directed arrows indicate the reuniting (mutual cancelation) of those forces.

Experiences arise in the cleft created when Nothing divides into future (expansion, yáng) and past (contraction, yin). They disappear when that cleft collapses, reuniting future and past into the Absolute Present of Nothing.

This special Nothing is known to contemplative traditions around the world.”

The particular aspect of diagrams that this series illustrates is the power diagrams have to communicate complexity.

I think it would be almost impossible for readers to understand Young’s ideas if they just had to rely on his textual explanation without also being able to see the graphical representations of his ideas.

Aspect 4: Making processes more tangible

Above is an example of a WalkThru diagram (which can also be categorised as an instructional graphic) created by Oliver Caviglioli on the subject of Class Attainment and Progress Meetings.

It appears in and illustrates ideas from Tom Rees’s book Wholesome Leadership: The Heart, Head, Hands & Health of School Leaders (John Catt Educational, 2018).

The other WalkThrus in the book are on the topics of Appraisal, Learning Walks and Review Mornings. All of them can be found at

These Walkthrus combine a timeline, text, pictorial illustrations and icons. They are all accompanied by more detailed text giving background information about each activity and tips about how to conduct it effectively.

There are many non-fiction books that provide processes to help readers participate in new activities or learn new skills. The problem authors have is how to motivate their readers to move from consuming knowledge to actually putting it into practice.

These instructional diagrams are valuable because they help to make processes that appear abstract on the page more tangible and encourage readers to start mentally rehearsing themselves doing that activity or learning that skill. This, I think, makes it much more likely that readers will move from thought to action.


The examples given in this blog post have shown different ways in which diagrams can provide clarity and understanding for non-fiction readers.

Diagrams allow readers to expend less cognitive energy deciphering the meaning of the text they are reading, which means they will have more cognitive energy available for the critically important tasks of understanding, assessment and reflection.

And, as I mentioned in the introduction, diagrams benefit not just readers but also authors.

For me personally, creating diagrams improves the clarity of my thinking. When I try to graphically map out the relationship between the different ideas or concepts, gaps in reasoning or a lack of clarity quickly become apparent.

I am sure that this is also the case for other writers.

The benefits of diagrams are many so let’s hope in the future that non-fiction books without diagrams become an increasingly rare occurrence.

Next steps

Some of the first work diagrams I created were flowcharts mapping the accounting processes of the Falklands Islands Government in the mid-1980s. Since then, I have often used diagrams to convey ideas, concepts and processes.

Please get in touch if:

a) you would like assistance in creating diagrams for your presentation, report or non-fiction book

b) you have a work or analytical process that you would like to formalise with the creation of a graphical model.

Further reading

I contributed a 4-page section on diagrams to Oliver Caviglioli’s 2019 book Dual Coding with Teachers. Click to read the pdf.

Note 1

The elements in a diagram can be represented in different ways, including:

  • as words (this can include both element names as well as more explanatory detail for individual elements)
  • as geometric shapes used as containers (rectangles and circles)
  • as pictorial illustrations
  • as icons
  • or as a combination of these.

The relationship between elements can also be represented in different ways, including:

  • through connectors, which can include:
    • lines with or without uni-directional or bi-directional arrows (further differentiation can be provided with dotted and dashed lines)
    • words describing the exact nature of the relationship
    • arithmetical symbols (eg. +, – and =)
  • through positioning, which can include:
    • the intersection of elements (as in Venn diagrams)
    • the adjacency of elements (ie. elements touching each other)
    • the alignment or lack of alignment of elements
    • showing elements with varying proximity/distance to each other
  • through other ways of conveying meaning
    • showing elements with different sizes/areas
    • using colour or shading
    • nesting elements
    • using brackets to show that multiple elements belong to a higher-level category.
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