Scale of Cognitive Tools
Disambiguation: common use of the term "cognitive tools" means learning with the aid of media / technology. Here, I am talking about tools that we use to support cognitive processes in a slightly more general meaning: thinking, remembering, creative cognitive work. As a hammer extends my hand and arm, cognitive tools extend my brain.
What makes Pen and Paper similar to, and different from, an Electronic Cash Register
Take a piece of paper and a pen. You can do everything with it. Well, Not Everything of course, but - let's see:
You can test if the pen works.
You can make a paper airplane.
You can make a shopping list.
You can write down the Theory of Everything once you found it.
You can make calculations that you can't make in your head, like a 20-digit division.
You can write a love letter to your darling.
You can make sketches or mind maps to sort out your thoughts when designing the implementation of a new feature for a computer program.
You can write down the melody of a song that you are composing.
Did you expect there to be so many things you can do with that? I probably missed a dozen other things that you can think of.
I am saying that pen and paper form a cognitive tool because they enable me to do a lot of things that Stephen Hawking could do in his head but that are just too visual, complex, tedious, or whatever to make that convenient for me.
By contrast, look at a cash register. With this, you can
- Calculate the total of the prices of items that someone wants to buy.
A cash register also is a brain extension tool: you could do that in your head.
Why would I ever prefer to use a cash register, when there are so many things I can do with pen and paper?
The cash register is of course optimized for a specific activity. Optimization might aim for reducing effort, potential for errors, potential for mischievous manipulation, and increase overall efficiency. Those are all good things.
When you single out a specific activity and optimize for that, or if you just choose a specific technology, you might be reducing the variety of uses for a thing. Sometimes you might even preclude some uses completely, e.g. giving rebates based on personal taste.
I would like to simplify the question to this scale:
Think about how you think. Which tools do you use? How do they facilitate, how do they inhibit specific ways of working?
Can a tool have the effect of limiting the thinking you do, because there are concepts that cannot be expressed with this tool?
Some examples from my experience:
Lilypond lets me write sheet music that is both precise and beautifully set, but I find it too cumbersome to deal with it when trying to find a tune on my guitar. I use paper for that.
In Visio I can make precise diagrams with a defined symbolic language in order to create long-lived documentation. When I am creating, designing, I often find it hard to even limit myself to a UML class diagram or sequence diagram at a time; I love whiteboards and big sheets of paper and more than one color.
In MindManager or FreeMind, it is relatively easy to make mind maps. In these tools, mind maps are limited to trees, however - even where it is possible to create links between branches, it is more effort. I feel that this can have the subtle effect of failing to record such associations, whereby they get lost for later analysis.
Of course, there's the right tool for the job. I'd like to emphasize, though: When you're looking for a tool to help with a specific acitivity, you can find pairs of tools A and B that both list that activity as an intended use, but one gives you more freedom than the other.
Be wary of the restrictions your tools impose on your thinking!