Having more tools greatly increases the space of potential plans you can consider. So by default you should be getting more tools. Having too few tools tightly constrains your options, and often impacts the kinds of plans you consider in the first place.
Years ago I thru-hiked the Appalachian Trail, and every piece of gear mattered. I had a lot of things when I first started out that seem very foolish to me now, things I wouldn't consider bringing again. For each piece of gear, I had to carry every gram of it 2200 miles, and so each gram had to earn its weight. I tossed or gave away almost everything that I wasn't using every single day by the end of the second week. The only exceptions were some band-aids and similar items to prevent the worst outcomes. When I fell and split open my knee, I used toilet paper to pack the wound, and some duct tape to secure it. It worked great while I continued to hobble along. Every piece of gear had to pay for its weight, and part of that was finding creative uses for the pieces I did have, to cover more functions. I spent a lot of time optimizing within the strict constraints I had: weight, pack volume, distribution of frequently-used items with once-a-day items. I paid for this optimization with some increased risk and a greatly narrowed space of things I could do while on the trail. That was fine then, because the only thing I was doing was hiking.
Nowadays I'm not carrying everything I own on my back, hiking 20 miles every day to get to the next town and resupply before I run out of food. So the constraints are really quite different! I can buy and store random things like a cheap multi-tool just to test the idea of having a multi-tool around, and purchase a high-quality one once I've gotten a sense of how much it's worth. When the cost of tools is so low, buying cheap tools can be a cost-efficient way to explore a new space of plans. The cheapness of tools is nice, but what I didn't expect was how much this mindset of extreme minimalism affected my thinking.
There were so many tiny things that I wasn't considering, merely because the tool to do them wasn't immediately available. When making simple plans I often use a simple algorithm and ask myself three questions: What do I have? What do I want? How can I use the former to get the latter? But this misses a step wherein I can get more tools to widen the space of plans!
For tools I am proficient with — asking myself the question, "What do I have?" naturally includes them. They became an extension of me to some degree. But for tools I'm not proficient in, using them (or even learning) doesn't cross my mind as part of a plan at all! Many tools are actually quite easy to learn, and the cost is low enough that I should have been making plans where I would consider them anyway, but I wasn't. Having a tool expands your plan space; being proficient makes that expansion automatic.
If I get a rip in my socks, sewing them back up by hand quickly and easily rises to my mind as one possible plan to fix this problem. Yet if I didn't have a needle or thread, or the very simple knowledge in how to use them, it wouldn't be a consideration. I have witnessed this many times when a friend bemoans a rip in their favorite jacket, and manually sewing it back up doesn't even cross their mind.
Or maybe it doesn't cross their mind because they don't know how to sew — not because they lack needle and thread. Yet I would bet if they had a needle and thread lying around, they might consider trying it before resorting to more expensive plans. The physical presence of a tool can be a cognitive prompt to use it.
Investing the time to become proficient in some general-purpose tools isn't just useful for a current project, but it increases the types of projects you can now undertake. I've talked a lot about physical tools, but this applies to tools for thought like calculus, statistics, programming, Excel, Photoshop, etc.
Many people are blocked more by the plans they're able to consider than by money. I think they should be spending more time on getting and learning to use new tools. Or phrased as a standard Umeshism: If you've never bought a tool you didn't need, you're not buying enough tools.
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