Workbook help: 10-19 Define your system’s scope

This post is for issues specifically and only to do with the Johnny.Decimal Workbook area: 10-19 Define your system’s scope.

14.02 The Decimal Workbook • Johnny.Decimal

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I have to apologize right at the beginning. I have not followed your advice and I am wondering what might be the consequences and should I go back. (system was built before I bought the workbook)

I am young (21) and have very little (like less than 50 indexable things) management worthy in my personal life and a fair bit in my own business. This system I designed and built within 8 hours from start to having all my files and index in order.

Can you tell me what might come up in the future if I did the designing too fast and without proper consideration?

Small look at my system structure:

00-09 System
  00 Johnny.Decimal
  01 Notes

10-19 Personal
  11 Contracts & Documents
  12 Study & Work
  13 Hobbies
  14 Media
  15 Estate(Translated from finnish so might sound weird but includes vehicles, houses, companies, important receipts) & Finance

20-29 My company
  21 Admin
  22 Projects
  23 Sales & Marketing
  24 Guides & Inspiration


At first glance this seems okay. I like how small it is: lots of room to grow in the future.

It can be hard when you don’t have that much to organise to put structure around it. Like, your sample size is too small. But that’s okay, just keep an eye on it over time and don’t be afraid to re-organise things at this early stage.

Hopefully you’ll have this system for decades. Changing it at the beginning is A-OK.

Thank you so much for the fast reply!

I really bought the idea of only 2 levels and simplify as much as possible - before I was the subfolder after subfolder guy and had no idea in which folder I had stuff stored.

Also I think that the index was a really great thing - for me it removes all my stress for trying to hold the knowledge of was this in onedrive or icloud or google drive or email or trello?

This feels super natural for me, I have a strong belief that this is the way to go.

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How? :wink:
I am 22 and have a lot more than 50 things…

Like what should I keep - I would not like to be a digital hoarder :smiley:

One reason for this “small amount of indexable things” is that I don’t go so granular about my index usage in most cases. For example I have used only one index for my pictures(which there are many but those are better organized with date).

I don’t think AC.ID as one file, rather that is a thing with many related files. For example I think it would be too big to create a category for upper secondary school files or university. Those only contain diplomas and stuff.

In my system those are ids and in total there are about 30 or so of these things. However if I calculate all files that I have stored, I think it would be around 2000 files.

In addition the kitchen painting example from Johnny has been really helpful. That makes me think that most of the things I handle are small enough to fit in ID:s. The fact that I have less than 50 AD.IC:s makes me believe that the system is big enough with the 10:10:100 structure.

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Whoops, maybe I am :slight_smile:

No me neither, an ID being a ‘thing’ with multiple files in my case as well.

Apologies in advance for any incoherence; I am not entirely sure I understand my problem sufficiently to explain it. I have taken on the task of sorting out about 40 years of data from three semi-separate organizations all operating under the same non-profit, with a single board of governors, and sharing several staff members. One of them is a 4-year college.

This is my third run of trying to get all of the parts and data and files defined into projects. On my first run, I landed on seven projects that looked good on paper, but as I began trying to work on different ones by themselves, I found that they were too integrated with other projects to be considered a separate things. Then I tried treating the entire non-profit as a single project, but the sheer amount of information quickly became too overwhelming. On the one hand, we are really really small - I’m the only secretary. On the other hand, we’re big enough that I’m pretty sure there’s at least two projects here, maybe three or four.

As far as I understand projects vs. areas, it seems as if the difference between the two could sometimes depend upon the amount of things that it needs to contain, which seems like it might scale up and down with an organization’s size. Going off that assumption, what are some markers that can help identify something as a whole project by itself vs. one part of a project?

Welcome. And, interesting problem!

So yes, you’re definitely larger than one ‘system’ (as we now call them[1]).

The classic thinking behind a system is that they’re isolated units without much in common. But that’s just the usual case; there’s nothing to say that it has to be so in your case.

The problem

Remember that one of the things that makes JD powerful is the fact that it limits you to 10×10: ten areas, each with ten categories. For most systems, that’s not only enough, it’s a powerful restriction that helps you to be organised.

But you couldn’t fit the whole world in to 10×10, so we have the ‘multiple systems’ notation where we prepend a ‘system code’. (Sorry for the confused parlance. We’ll be updating everything asap.)


Systems don’t have to be isolated

In your case, you can stop thinking about these as separate projects systems and instead think about this extended numering as just that: an extension. Your use-case requires more, so give yourself more.

The trick here is in identifying patterns across the 3 organisations. If they’re all of a similar nature, they’ll all have similar needs. For example they might all have (suggested JD categories in red):

  • Staff, and hence payroll
  • A physical building, and hence maintenance
  • Tax and other regulatory compliance.

If you can identify these patterns and build one common area, say, that each org can then get its own copy of, you’ll be in a much nicer place.

Each org will also surely have its own areas that are unique. So you just design those per org/system.

And over the top you might have another system for the governing structure. Because it doesn’t sit within any of the 3 orgs, it encompasses them all. So you might end up with this very simplified idea.

If some of these systems – say the COMMON one – only have one area, that’s totally fine. That might well be all they need. Don’t be shy of sparsely populated systems.

Use semantic SYS identifiers

In this case it’s probably worth using three letters, based I guess on the existing name/geography of the place? Because then let’s say you have CHI, NYC and LAX just as geographies that we all understand.

If this works out, you’ll be in the nice situation where CHI.21.03 is the staff plan for Chicago, and we all already know where the staff plan for NYC is.


I’ve tried alternatives in the past. At a previous job the scope was so large that it really didn’t fit in to 10×10 so I expanded the numbering, using 3 digits for my categories. So 101.11 would have been an ID inside category 101, inside area 100-199.

This is an option, but I suggest trying out the first idea first. The extended numbering worked but I don’t recall loving it.

Let us know how you get on!

  1. Lucy is updating the Workbook with this new terminology literally right now. She’s almost finished and the 4th edition will be released in the next few days. ↩︎

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Hi there I arrived here on a whirlwind after happening across a comment on this reddit post

I was so excited by the idea of everything being organised and impressed by the system that I quickly bought and have read through the workbook once.

I have come now to defining my system scope and have encountered an initial decision that I’m struggling with, whether to have one or two systems.

I currently have a fair amount of old data that I would like to organise (at least anything useful) from University and other projects and work. I have all the personal things people have. The thing that I’m not sure on is I’m starting to develop a brand with a website, youtube, instagram. The amount of stuff is going to continue increasing that I have to organise. ultimately I want to run my own business - a farm where I will research and promote new regenerative and sustainable farming methods.

Currently though, I think if I had one system and didn’t really exclude anything then I would be able to fit everything in, pure personal stuff and ‘mission’ stuff.

My question is whether it would be better to start with one system and promote a ‘mission’ area later if it got too big, or to start with two systems from the start with all the extra set-up and perhaps redundancy that might cause.

I’m thinking for now I’ll start as though I’ll do one system, make a lot of sticky notes ect, then if it becomes clear that fitting it in will be difficult, I’ll switch to making two systems (at the same time?).

Any thoughts would be much appreciated. I really just want to get stuck in and start making something at this point haha!

Do this! For sure. (And, welcome.)

As an example, Johnny.Decimal was 50-59 in my personal area for a long time. 10 categories of things with 100 items in each is a lot of room to grow a thing. It took a decade for it to be promoted to its own system.

One system is vastly simpler to manage.

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@johnnydecimal Thank you so much, one system it is!

On a follow up note, are there some things that I should exclude from a personal system scope?

In this case any work related stuff is closely linked to my personal things so excluding any of that wouldn’t make sense.

Otherwise there are only things that I wasn’t putting into my old ‘system’. Things that people say that I don’t need to concern myself with or other people’s work which I don’t want to take on. It seems obvious that anything like this wouldn’t go into my system, but perhaps its worth writing down anyway.

I may have answered my own question but if you have any thoughts they will be appreciated.

You’re on the right track. If it’s really obvious, it’s probably not worth noting.

When we recorded this bit of the workshop I emphasised to Lucy that it’s the areas of ambiguity that are probably the more interesting.

Hey @johnnydecimal thank you so much for putting together an amazing system. I read through the core areas and concepts on the website when I stumbled across the JD system in a random Reddit comment looking to organize things for PKM in Obsidian. After spending about an hour on the website, I was convinced that this is going to be a great way to manage my life’s information organizational needs!

Realized you have a workbook and a workshop so got psyched and signed up! I’m now working my way through the workbook and have landed on the scope definition. Leaning on your advice, I’m going to give it a few days to marinate to capture things that should be within and outside scope so that I don’t have to backtrack later on.

I did have a question though on whether professional work (day-time job) can live within a system that is shared with personal life admin, home business, etc. For context, there are thematic and knowledge elements that have overlaps between the day-time and home businesses, not that it would have a bearing (I imagine … ) in how the areas are set up but for now I’ve put the day-time job in the unsure box in the 93.02 worksheet.

Thoughts on what might be a good way to organize or reason through that? For some more context, the day-time job comes with standard things like client engagements, emails, meeting notes, writing and publishing articles, internal research, etc. (it is a management consulting job)


Hmmm my gut feel is that the day job is a separate thing.

Unless you think you could comfortably fit it in to a single area? And from what you’ve said here, it doesn’t sound like that’s the case.

…but let’s think about this. We don’t know until we know, right? So perhaps you leave it in scope, you do the rest of the exercises, and later on if it feels too big, then no harm has been done: you can just decide at that point to split the systems. You don’t need to decide until 40-49 Build your system.

Whereas if you leave it out now, it won’t be included in discovery and you’ll never know.

How’s that for a change of position! Total 180° reversal in opinion in one short post. Strong opinions weakly held and all that.

Edit: yeah but my caution would be, later on, don’t try to shoe-horn it in to one area just to make it fit. If it doesn’t fit, it doesn’t fit.

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Thank you @johnnydecimal for the swift reply. OK that approach makes a ton of sense. Will keep marching on then. Bullets rather than cannonball approach is a good mechanism to allow steering and course correction.

I went through a bit more material in the interim and it’s definitely a journey rather than a fast, onetime, done and dusted thing as go through the discovery process.

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A few months ago I asked JD some help because I have a busy life with so much stuff going on that would require AT LEAST 3 different system, if not more.

JD reply annoyingly that I should try to fit everything in one system.

IMPOSSIBLE!!! What does he knows, really about my complicated little life…

So, after a few months of trying to figure it out, I kind of have everything fit into one system… with a lot of room to grow…. And it is much less complicated.

But yeah maybe … :wink:
With all my gratitude to Johnny!



Ha! Great news. :hugs:

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