Ideas come to all of us. The trouble is, if we don’t write them down, they’re gone, and before long, we’ve forgotten they ever came.

I was going to give you an example of an idea I failed to write down. But I can’t. I’ve forgotten it.

That’s the problem in a nutshell. A lost idea leaves no trace—not even the memory of losing it. You can’t miss what you can’t remember having. All you’re left with is the suspicion that, once, you were cleverer than you are now.

What the notebook people knew

I read Roland Allen’s The Notebook: A History of Thinking on Paper for the second time just a few months back, it’s one of my favourite books. It’s full of people who understood this. Leonardo’s pages jumble sketches of machines with shopping lists and studies of water. He didn’t wait for the finished thought. He put down the half-formed one, the odd observation, the question he couldn’t yet answer.

Then there’s Darwin. He sailed around the world for about five years and did his fieldwork with the smallest, scrappiest notebooks imaginable. He’d take long excursions ashore and fill these tiny notebooks with almost indecipherable notes: no punctuation, poor handwriting, no full sentences.

But after a few days or weeks, he’d take those rough, disjointed notes and transform them into full prose, detailed diagrams and well-structured observations. Over the course of the voyage he filled 14 of these tiny notebooks, so small you could fit them all in a shoebox with room to spare. Those notes became the foundation for his theory of evolution by natural selection.

Without notebooks, could he have done it? Probably not.

What strikes me is how seemingly insignificant the notes were at the time he made them.

But Charles didn’t fool himself. He knew he’d forget otherwise.

Your memory isn’t as good as you think

However good you think your memory is, you will not remember. I’d bet Darwin’s was a good one, and yet he still filled 14 notebooks.

An observation from March may only become important in September, but that can’t happen if the first one has already gone.

You don’t need a grand system to avoid losing it. You just need to make catching a thought so easy that there’s no excuse for letting it go.

What I do

The trick is to have something to hand wherever you happen to be. For me, that depends on where I am.

Most things go into WorkFlowy and TheBrain. WorkFlowy is on my phone, so if I’m out and about, or stuck in a queue, that’s what comes out of my pocket. At the Mac, TheBrain 14 has a feature called Quick Thoughts, which pops up a little note window from anywhere, so I can catch a thought without leaving what I’m doing. It also has a Safari extension for quick capture while I’m browsing. TheBrain is my main depository, where everything ends up.

On the boat it’s a pen and a small notebook, which I carry everywhere. Phones and salt water don’t mix, and a pen never runs out of battery. On my walks I use a little voice recorder, since you can’t write while you’re walking and the best thoughts tend to turn up when you’re on the move. I process those recordings as soon as I’m back indoors, while I can still remember what I meant.

Given that I don’t have my phone or laptop in the bedroom, I use a digital analogue Kobo tablet instead. Although it’s primarily for reading, it also lets me write notes and is backlit. Perfect for jotting down those (rare) early hours strokes of genius without disturbing Gail.

One thing I insist on is that wherever the digital notes are made they must be exportable in Markdown format. It’s really just plain text with a little light formatting, so it will open in almost anything. That means I can move my notes into other software, and file them away safely, without being held hostage by any one app. Apps come and go. I’m nearly seventy, and I’ve watched a lot of them go. Plain text has outlived all of them.

Go back to it

Catching an idea isn’t quite enough. You have to look at it again.

I do my review the morning after, and I go through the notebook entries at the same time as the digital ones. The thought is still fresh enough to make sense of, and I can usually tell at a glance what was a passing fancy and what’s worth keeping. It doesn’t take long.

Darwin did the same, in his way. His scrappy field notes only became useful when he turned them into proper prose and diagrams a few days or weeks later.

Leaving notes unvisited is the same as forgetting. A thought you wrote down and never looked at again is no more use than one you never wrote down. It’s just harder to notice that you’ve lost it.

A word on what this isn’t

You might be wondering how I organise all this, and what I do with the ideas once they’re caught. That’s a big subject, and the waters of personal knowledge management are strewn with reefs. I’m not going to sail into them today. I’ll chart them another time. For now, this is only about getting ideas out of your head and onto something that will keep them.

Write it down

So if you take one thing from this, make it the habit rather than any particular app or notebook. When something catches your attention, get it down before it goes. Look at it again soon after. Keep it somewhere you’ll be able to find it, and in a form that will still open in ten years’ time.

You will not remember. Write it down.