How To Improve General Knowledge

Everyone knows one of these people. Somebody mentions the Suez Canal, or mitochondria, or why the Dutch got so tall in one century, and this person has something to add. Not a lecture. One clean fact that moves the conversation forward, and then they hand it back to you.

The usual assumption is that they read more than you do. Most of the time they don't. They keep more of what they read.

That difference matters, because it changes the fix. You probably don't need a longer reading list. You need a way to hold on to what already passes through your head every week.

The short version: to improve your general knowledge, learn in small daily doses instead of long rare sessions, test yourself instead of re-reading, follow the topics you are actually curious about, and come back to them a few days later. Ten minutes a day beats two hours on a Sunday, and the research on why is close to a century and a half old. Micro Learning Apps like my own brand NerdSip help with that.

Why almost nothing you consume sticks

In 1885, Hermann Ebbinghaus sat down with lists of nonsense syllables and tested himself at intervals, on himself, for years. He found that forgetting is brutal at the start and gentle afterwards. Around two thirds of fresh material was gone inside a day. Whatever survived that first day tended to hang around far longer.

People love to wave this away as a Victorian curiosity. In 2015, Jaap Murre and Joeri Dros ran a careful replication in PLoS ONE and got the curve back almost exactly.

Meaningful material decays more slowly than nonsense syllables, so don't take the number too literally. Take the shape of it seriously, because the shape is the whole problem. You listen to a two hour podcast on Roman engineering, you feel informed, and by Thursday you have one anecdote left and no idea whether it is true.

The feeling of learning and the fact of learning are different things. That gap is where most self-improvement effort quietly dies.

Rule 1: small and daily beats big and rare

The spacing effect is one of the most replicated findings in psychology. Nicholas Cepeda and colleagues reviewed 254 studies covering more than 14,000 participants and found the same thing across nearly all of them: the same total study time, broken into separated sessions, produces substantially better long term retention than one massed block.

Your brain does real work between sessions. Cramming skips that work and gives you a warm feeling of competence instead.

So the practical unit is ten minutes, most days. Sixty-something hours a year of focused learning, which is more than most people manage in the two-hours-on-Sunday plan they abandon in February.

The hard part is never the ten minutes. It is remembering to start. Two things help.

First, anchor it to something you already do without thinking. Coffee, commute, the ten minutes after you put the kids down. Peter Gollwitzer and Paschal Sheeran's meta-analysis of 94 studies found that "when situation X happens, I will do Y" plans have a medium to large effect on whether people follow through. Vague intentions do not.

Second, plan for it to take a while. Phillippa Lally's team tracked 96 people forming everyday habits and found a median of 66 days to reach automaticity, with a range from 18 to 254 days. The famous 21 day rule has no study behind it at all. If your new habit feels effortful in week three, that is the normal case, not a failure.

I wrote a longer, day by day version of this in my guide on the Nerdsip Blog how to improve your general knowledge including what to do on the days you have no energy for it.

Rule 2: test yourself, because re-reading is a con

This is the rule that changes the most for the least effort.

Henry Roediger and Jeffrey Karpicke gave students a prose passage. One group reread it repeatedly. The other read it once and then took recall tests. Immediately afterwards, the rereaders felt more confident and did slightly better. A week later the tested group recalled about 61 percent of the material and the rereaders about 40 percent.

Karpicke and Janet Blunt later ran retrieval practice against elaborative concept mapping in Science and got the same verdict. Testing won, and students predicted the opposite.

In 2013, John Dunlosky and colleagues graded ten popular study techniques for Psychological Science in the Public Interest. Practice testing and distributed practice came out as the only two rated high utility. Highlighting, rereading and summarising were rated low. Those are, of course, the three things almost everyone does.

The reason is fluency. When you reread, the text feels easy, and your brain reads that ease as knowing. Recognition is not recall. "I have heard of the Antikythera mechanism" and "I can tell you what it did" are separated by a gap you cannot see from the inside until someone asks.

The fix costs nothing. After anything you read or watch, close it and say three things out loud. Whatever you cannot say is the part you never had.

Rule 3: follow the interest, not the obligation

There is a certain kind of person who decides to become well informed and starts with a list of things a well informed person is supposed to know. It almost never survives contact with a Tuesday.

Matthias Gruber, Bernard Gelman and Charan Ranganath put people in a scanner and showed them trivia questions they had rated for curiosity. High curiosity states came with activity in the midbrain and nucleus accumbens, the dopamine regions, and memory improved for the answers people wanted. The interesting part is what else improved. Faces shown during those curious states, completely unrelated to the trivia, were also remembered better a day later.

Curiosity is not a mood you wait for. It is a state that makes the next twenty minutes of your brain work better, including for material you were not even aiming at.

So chase the thing that hooked you. If a documentary about deep sea cables sends you sideways into shipping law, go. General knowledge is a network, not a syllabus, and the messy self-directed route builds more connection points than the respectable one.

Rule 4: use it, or watch it drain away

Two ways to lock something in, both cheap.

Come back to it. A single revisit two or three days after you first learned something does more than an extra half hour on day one, for the same reason the spacing effect works at all. This is what people mean by spaced repetition, and it does not require software. A note on your phone works.

Then tell someone. John Nestojko and colleagues had students study a passage, telling one group they would be tested and the other that they would teach the material to another student. Nobody actually taught anything. Everyone got tested. The group who expected to teach recalled the passage more completely and more coherently, especially on main points. Just expecting to explain it changed how they read.

This is the same finding at classroom scale that Scott Freeman's team reported in PNAS in 2014. Across 225 studies of undergraduate STEM courses, active learning raised exam performance by 0.47 standard deviations and cut failure rates from around 34 percent to 22 percent. Sitting and receiving is the weakest thing you can do with your attention.

Louis Deslauriers and colleagues added the sting in 2019, also in PNAS. Students in active classes learned more and felt like they had learned less, because the effortful version is less comfortable than a smooth lecture. Trust the outcome, not the feeling.

## The five minute version you can run today

1. Pick one topic you are genuinely curious about right now. Not one you think you should care about.

2. Learn for ten minutes, then close everything.

3. Say three things you remember, out loud, with the screen off.

4. Tell one person one thing you learned today.

5. Put a note in your calendar to revisit the same topic in three days.

6. Tomorrow, do it after the same cup of coffee.

That is the entire system. Everything above is just the evidence for why those six lines work.

## What ten minutes a day actually adds up to

Ten minutes a day is roughly sixty hours a year of deliberate learning. But the hours are not really the point.

The point is 365 hooks. Every fact you keep gives the next one somewhere to attach, which is why knowledge accumulates faster the more of it you have. The person who seems to know something about everything is not smarter than you. They are three years into the compounding and you are on day one.

Day one is fine. Day one is the only place anyone starts.

Common questions

How can I improve my general knowledge fast?

Faster than you think, but not the way most people try. Consistency beats intensity: ten minutes daily for a month will leave you with far more than a single weekend of hard reading, because the spacing between sessions is doing half the work.

What is the best way to remember what I learn?

Self-testing plus a delayed revisit. Recall it with everything closed, get it wrong, then look it up. Being wrong and corrected is one of the most efficient things that can happen to your memory.

Do I need to read books to have good general knowledge?

No. Books are excellent and slow. Articles, documentaries, good podcasts and short courses all work, provided you do something active with the material afterwards. The format matters far less than whether you ever retrieve it.

How long before this feels automatic?

Expect two to three months, based on Lally's median of 66 days. Missing a day does not reset anything, which that study also found. Missing three weeks does.

Is general knowledge still worth having when I can look anything up?

Looking things up requires knowing that the thing exists. Broad knowledge is mostly a map of what questions are available to ask, and no search engine hands you that.

A shortcut, and a disclosure

I built an app for this, so treat the next paragraph accordingly.

NerdSip is a micro learning app that runs the four rules without you having to think about them. Courses are short enough to finish in about five minutes, every lesson ends in a question so you are retrieving instead of skimming, you can type any topic and get a course built for it, and finished material comes back around later instead of vanishing. Streaks handle the boring consistency part. It is free to start.

You do not need it. You need ten minutes and the discipline to close the tab and say three things out loud. But if the discipline is the part that keeps failing, structure helps.

I made a short video walking through the same four rules if you would rather watch than read:

https://www.youtube.com/watch?v=x02HFGGK_pU

And there are more general knowledge guides on the site, including the retention research, the questions worth knowing, and why so many capable people feel like they missed the basics.

Start today. Pick the topic that already has your attention.

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## References

- Ebbinghaus, H. (1885). Über das Gedächtnis. Duncker & Humblot.

- Murre, J. M. J., & Dros, J. (2015). Replication and analysis of Ebbinghaus' forgetting curve. PLoS ONE, 10(7), e0120644.

- Cepeda, N. J., Pashler, H., Vul, E., Wixted, J. T., & Rohrer, D. (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis. Psychological Bulletin, 132(3), 354-380.

- Gollwitzer, P. M., & Sheeran, P. (2006). Implementation intentions and goal achievement: A meta-analysis of effects and processes. Advances in Experimental Social Psychology, 38, 69-119.

- Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W., & Wardle, J. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998-1009.

- Roediger, H. L., & Karpicke, J. D. (2006). Test-enhanced learning: Taking memory tests improves long-term retention. Psychological Science, 17(3), 249-255.

- Karpicke, J. D., & Blunt, J. R. (2011). Retrieval practice produces more learning than elaborative studying with concept mapping. Science, 331(6018), 772-775.

- Dunlosky, J., Rawson, K. A., Marsh, E. J., Nathan, M. J., & Willingham, D. T. (2013). Improving students' learning with effective learning techniques. Psychological Science in the Public Interest, 14(1), 4-58.

- Gruber, M. J., Gelman, B. D., & Ranganath, C. (2014). States of curiosity modulate hippocampus-dependent learning via the dopaminergic circuit. Neuron, 84(2), 486-496.

- Nestojko, J. F., Bui, D. C., Kornell, N., & Bjork, E. L. (2014). Expecting to teach enhances learning and organization of knowledge in free recall of text passages. Memory & Cognition, 42(7), 1038-1048.

- Freeman, S., et al. (2014). Active learning increases student performance in science, engineering, and mathematics. PNAS, 111(23), 8410-8415.

- Deslauriers, L., McCarty, L. S., Miller, K., Callaghan, K., & Kestin, G. (2019). Measuring actual learning versus feeling of learning in response to being actively engaged in the classroom. PNAS, 116(39), 19251-19257.