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Mental models

Mental models are a valuable tool for engineers.

I do engineering as a day job. Often diagrams, drawings, and other visuals will be created to help convey information to customers and facilitate discussions. Visuals, while always leaving out some details, and in fact the challenge of creating visuals being knowing what details to leave out, helps immensely with audience engagement.

gitGraph commit commit branch feature commit commit commit checkout main commit commit merge feature
A random git feature branch development model diagram

A visual's layout, colors, blocks, arrows etc are far easier to consume than a wall of text. In spite of their relative simplicity when compared to text, they can be constructed to represent complex systems, relationships, processes etc.

We create a lot of visuals to help convey information to others, are we using them enough when conveying information to ourselves?

stateDiagram direction LR state "Mental Model" as mm Idea --> mm Idea --> Visualization mm --> Idea mm --> Visualization Visualization --> mm Visualization --> Idea

How can you make better use of visuals?

Sketch them out

I like to keep scrap paper around for notes, sketches etc. Sketching or drawing on paper, even if you end up tossing the paper out later, lets you quickly iterate on a visual, often much more quickly than making use of a tool like Visio, PowerPoint etc. If you've got an iPad with a stylus or some other electronic drawing tool that can work too. The imporant part is that it has to be quick and not feel permanent. Quick means its easy to get started and stop. Non-permanent allows you to take more risks and be less concerned with perfection.

Make visuals anytime when you don't have a clear mental model

I find that for many cases I can build a mental model of a system or a design by listening to someone explain the design in words. Often that's what I'm doing as I'm listening to someone describe a potential product, a software class, or an approach of code or data structure. It isn't about whether my mental model exactly matches theirs but rather that my mental model includes clearly the aspects that are critical to the topic at hand.

This can work if the person explaining it can do so clearly, and if the system is sufficiently simple. If the discussion is to help determine how to design something it may not be clear to the person explaining it. It may also be complex and multi layered. As soon as this occurs I find it helpful to apply the 'sketch it out' approach on paper, and/or ask the person to try to draw or sketch it out themselves.

Conclusion

I hope that this might encourage you to make even more use of visualizations. I'm no graphic artist or designer by any means. However I still enjoy putting together visuals, especially when they help to explain concepts and ideas to others.

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