How to Take Smart Notes - Summary, Notes and Highlights

How to Take Smart Notes - Summary, Notes and Highlights

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One of the key books on how to take notes. This book predates How to Build a Second Brain

These are my notes and highlights from the book How to Take Smart Notes by Sönke Ahrens.

🤔 What Is This Book About?

A lot of the notes we end up taking end up in notebooks on dusty bookshelves never to be seen again. Everything we learn from books, podcasts, and articles is just lost. Our brain can’t remember everything.

However, Niklas Luhmann managed to find a way to take smarter notes that allowed him to write 58 books and hundreds of articles in his lifetime.

👤 Who Should Read It?

Anyone who wants to be more creative and put to use the ideas and thoughts that they gain from books.

This is great for students, bloggers, YouTubers and writers. What to write about doesn’t come from your mind it comes from your notes.

📒 Summary & Notes


We write down not only those things we fear we won’t remember otherwise, but also the very things we try to memorise. Every intellectual endeavour starts with a note.

Everything You Need to Know

We suffer from procrastination and lack of motivation when staring at a blank page because we have to use our memory to try and come up with topics to write about.

With the right workflow in place, we don’t need to generate new ideas, the ideas come from the associations between our past ideas.

Still, we often struggle the most with procrastination and motivation. It is certainly not the lack of interesting topics, but rather the employment of problematic work routines that seems to take charge of us instead of allowing us to steer the process in the right direction. A good, structured workflow puts us back in charge and increases our freedom to do the right thing at the right time.

To try and mingle ideas it is important to immerse yourself in different disciplines. It is here we can find truly unique ideas.

Good students also look beyond the obvious. They peek over the fences of their own disciplines – and once you have done that, you cannot go back and do what everyone else is doing, even if you now must deal with heterogeneous ideas that come without a manual on how they might fit together. All that means is that a system is needed to keep track of the ever-increasing pool of information, which allows one to combine different ideas in an intelligent way with the aim of generating new ideas.

Poor students don’t know what they don’t know and come to the conclusion that they no everything. Good students make an effort and realise that there is a lot to know and underestimate what they do know.

Dunning-Kruger effect (Kruger and Dunning, 1999). Poor students lack insight into their own limitations

That means that those who are not very good at something tend to be overly confident, while those who have made an effort tend to underestimate their abilities.

Complexity builds up by itself the more you add notes to the system and add associations to other notes. Side-note: The Graph view in Obsidian would be helpful for this.

The simplicity of the structure allows complexity to build up where we want it: on the content level. There is quite extensive empirical and logical research on this phenomenon (for an overview: cf. Sull and Eisenhardt, 2015). Taking smart notes is as simple as it gets.

You need to get into a habit of taking notes and going through the process of making them permanent notes.

Even the best tool will not improve your productivity considerably if you don’t change your daily routines the tool is embedded in, just as the fastest car won’t help you much if you don’t have proper roads to drive it on.

Empty your mind onto paper. If you start with a clear mind your mind is free to make up connections and new ideas.

Only if we know that everything is taken care of, from the important to the trivial, can we let go and focus on what is right in front of us. Only if nothing else is lingering in our working memory and taking up valuable mental resources can we experience what Allen calls a “mind like water”-the state where we can focus on the work right in front of us without getting distracted by competing thoughts.

Success is down to strong working environments and routines, not willpower. Successful people don’t leave things up to willpower and motivation.

Strictly speaking, Luhmann had two slip-boxes: a bibliographical one, which contained the references and brief notes on the content of the literature, and the main one in which he collected and generated his ideas, mainly in response to what he read. The notes were written on index cards and stored in wooden boxes.

The notes should contain ideas, not information. If it does contain information it should be your own understanding of the work.

But, as I will explain later, they are quite different and it would be rather misleading to think of his slip-box as a personal Wikipedia or a database on paper.

Everything You Need to Do

You need to write to be able to think.

“Notes on paper, or on a computer screen … do not make contemporary physics or other kinds of intellectual endeavour easier, they make it possible,” neuroscientist Neil Levy

Do not brainstorm for a topic. Look into the slip-box instead to see where chains of notes have developed and ideas have been built up to clusters.

Everything You Need to Have

Keep it simple.

There is this story where NASA tried to figure out how to make a ballpoint pen that works in space. If you have ever tried to use a ballpoint pen over your head, you have probably realised it is gravity that keeps the ink flowing. After a series of prototypes, several test runs and tons of money invested, NASA developed a fully functional gravity-independent pen, which pushes the ink onto the paper by means of compressed nitrogen. According to this story, the Russians faced the same problem. So they used pencils (De Bono, 1998, 141). The slip-box follows the Russian model: Focus on the essentials, don’t complicate things unnecessarily.

The Four Underlying Principles

1. Writing Is the Only Thing That Matters

If you change your mind about the importance of writing, you will also change your mind about everything else. Even if you decide never to write a single line of a manuscript, you will improve your reading, thinking and other intellectual skills just by doing everything as if nothing counts other than writing.

2. Simplicity Is Paramount

To achieve a critical mass, it is crucial to distinguish clearly between three types of notes:

  1. Fleeting notes, which are only reminders of information, can be written in any kind of way and will end up in the trash within a day or two.
  2. Permanent notes, which will never be thrown away and contain the necessary information in themselves in a permanently understandable way. They are always stored in the same way in the same place, either in the reference system or, written as if for print, in the slip-box.
  3. Project notes, which are only relevant to one particular project. They are kept within a project-specific folder and can be discarded or archived after the project is finished.

3. Nobody Ever Starts From Scratch

Usually people start with note-taking to come up with new notes but you should use the knowledge in your slip-box instead.

You shouldn’t try and come up with a topic to write about and then do the research. The topic comes from your notes and then you already have all the research done

As proper note-taking is rarely taught or discussed, it is no wonder that almost every guide on writing recommends to start with brainstorming. If you haven’t written along the way, the brain is indeed the only place to turn to.

These study guides, which neglect everything before a writing assignment is given, are a little bit like financial advisors who discuss how 65-year-olds can save for retirement.

4. Let the Work Carry You Forward

Sometimes we feel like our work is draining our energy and we can only move forward if we put more and more energy into it. But sometimes it is the opposite. Once we get into the workflow, it is as if the work itself gains momentum, pulling us along and sometimes even energizing us. This is the kind of dynamic we are looking for.

Any attempts to trick ourselves into work with external rewards (like doing something nice after finishing a chapter) are only short-term solutions with no prospect of establishing a positive feedback loop. These are very fragile motivational constructions. Only if the work itself becomes rewarding can the dynamic of motivation and reward become self-sustainable and propel the whole process forward (DePasque and Tricomi, 2015).

He goes on to say that someone who rewards themselves for woking out by relaxing on the sofa will no doubt eventually skip the workout. You have to enjoy the process.

Feedback loops are not only crucial for the dynamics of motivation, but also the key element to any learning process. Nothing motivates us more than the experience of becoming better at what we do. And the only chance to improve in something is getting timely and concrete feedback.

Ironically, it is therefore often the highly gifted and talented students, who receive a lot of praise, who are more in danger of developing a fixed mindset and getting stuck. Having been praised for what they are (talented and gifted) rather than for what they do, they tend to focus on keeping this impression intact, rather than exposing themselves to new challenges and the possibility of learning from failure. Embracing a growth mindset means to get pleasure out of changing for the better (which is mostly inwardly rewarding) instead of getting pleasure in being praised (which is outwardly rewarding).

Praise them for what they have done not what they are (gifted).

The slip-box is not a collection of notes. Working with it is less about retrieving specific notes and more about being pointed to relevant facts and generating insight by letting ideas mingle. Its usability grows with its size, not just linearly but exponentially.

But we know today that the more connected information we already have, the easier it is to learn because new information can dock to that information.

But if facts are not kept isolated nor learned in an isolated fashion, but hang together in a network of ideas, or “latticework of mental models”(Munger, 1994), it becomes easier to make sense of new information.

The Six Steps to Successful Writing

1. Separate and Interlocking Tasks

The second is what psychologists call the [[mere-exposure effect]]: doing something many times makes us believe we have become good at it–completely independent of our actual performance (Bornstein 1989). We unfortunately tend to confuse familiarity with skill.

Problem-solving is about being flexible with how your work. You can’t always solve problems with lots of focus.

“Specifically, the problem-solving behavior of eminent scientists can alternate between extraordinary levels of focus on specific concepts and playful exploration of ideas. This suggests that successful problem solving may be a function of flexible strategy application in relation to task demands.” (Vartanian 2009, 57)

To become a master at something you need to go beyond what can be taught.

According to the Dreyfuses, the correct application of teachable rules enables you to become a competent “performer” (which corresponds to a “3” on their five-grade expert scale), but it won’t make you a “master” (level 4) and certainly won’t turn you into an “expert” (level 5).

To clear your mind and start working on what is important you need to get everything out on paper.

This is why David Allen’s “Getting things done” system works: The secret to having a “mind like water” is to get all the little stuff out of our short-term memory.

2. Read for Understanding

It is important to take notes while reading to make sure you understand what you are reading. You can then refer to these later instead of having to read the whole book again.

“I would advise you to read with a pen in your hand and enter in a little book short hints of what you feel that is common or that may be useful; for this will be the best method of imprinting such portcullis in your memory.” – Benjamin Franklin

And more often than not, reading is not accompanied by taking notes, which is, in terms of writing, almost as valuable as not having read at all.

Taking notes by hand increases your understanding of what you are learning.

Confirmation bias can stop us from taking in what we are reading unless it already confirms what we already believe.

The very moment we decide on a hypothesis, our brains automatically go into search mode, scanning our surroundings for supporting data, which is neither a good way to learn nor research. Worse, we are usually not even aware of this confirmation bias (or myside bias) that surreptitiously meddles with our life.

Read with your slip box in mind so that you can connect your thinking with what you are reading and learning.

The slip-box forces us to be selective in reading and note-taking, but the only criterion is the question of whether something adds to a discussion in the slip-box. The only thing that matters is that it connects or is open to connections. Everything can contribute to the development of thoughts within the slip-box: an addition as well as a contradiction, the questioning of a seemingly obvious idea as well as the differentiation of an argument.

Focus on writing what you read in your own words. Rereading tricks our brains into thinking we know something.

This is why choosing an external system that forces us to deliberate practice and confronts us as much as possible with our lack of understanding or not-yet-learned information is such a smart move. We only have to make the conscious choice once.

3. Take Smart Notes

Luhmann’s slip-box contains about 90,000 notes, which sounds like an incredibly large number. But it only means that he wrote six notes a day from the day he started to work with his slip-box until he died.

Use your slip-box as a way to store the information you want to refer to later. Our brains aren’t designed for storing information but for making connections.

The brain, as Kahneman writes, is “a machine for jumping to conclusions” (Kahneman, 2013, 79). And a machine that is designed for jumping to conclusions is not the kind of machine you want to rely on when it comes to facts and rationality–at least, you would want to counterbalance it.

When he spotted Feynman’s notebooks, he said how delighted he was to see such “wonderful records of Feynman’s thinking.” “No, no!” Feynman protested. “ They aren’t a record of my thinking process. They are my thinking process. I actually did the work on the paper.” “Well,” the historian said, “the work was done in your head, but the record of it is still here.” “No, it’s not a record, not really. It’s working. You have to work on paper, and this is the paper.

There was a man who could remember everything that he ever read or was told to him word for word. However, he lacked the ability to summarise what he had learned and make new connections from it.

It should be obvious that for academic thinking and writing, the gift of being able to remember everything is a serious liability.

Our minds have the ability to remember everything but it is more of a liability. We are able to think and solve problems because we aren’t having to remember everything.

Forgetting, then, would not be the loss of a memory, but the erection of a mental barrier between the conscious mind and our long-term memory. Psychologists call this mechanism active inhibition (cf. MacLeod, 2007).

To be able to truly learn something you need to understand how it works and this often involves linking it with other knowledge in your brain.

4. Develop Ideas

Use your slip-box as a way to find ideas to write about.

We don’t need to write anything down just to bridge a gap in a note sequence. We only write if it helps us with our own thinking. The gaps we do need to concern ourselves with are the gaps in the arguments in the final manuscript–but these gaps will only become obvious in the next step, when we take the relevant notes for an argument out of the network of the slip-box and sort them into the linear order for the rough draft.

Instead of thinking of keywords to group notes together, we need to think of them as ideas and link them together by lines of thought.

As writers, we approach the question of keywords differently. We look at our slip-box for already existing lines of thought and think about the questions and problems already on our minds to which a new note might contribute.

Keeping notes in groups stops you from linking everything together.

Observations like these could never be done nor explained by someone who is working with a system that keeps things neatly separated by preconceived themes and topics.

You have got to link new knowledge with existing knowledge in your head to truly remember and understand it. There is no point in learning isolated facts.

Charlie Munger writes: “Well, the first rule is that you can’t really know anything if you just remember isolated facts and try and bang ’em back. If the facts don’t hang together on a latticework of theory, you don’t have them in a usable form. You’ve got to have models in your head. And you’ve got to array your experience, both vicarious and direct, on this latticework of models. You may have noticed students who just try to remember and pound back what is remembered. Well, they fail in school and in life. You’ve got to hang experience on a latticework of models in your head.” (Munger 1994).

Creative people are better at recognizing relationships, making associations and connections and seeing things in an original way—seeing things that others cannot see“ (Andreasen 2014).

You need to think in abstract terms about the problems you are trying to solve. it is when you think in abstracts that you can see if the problem relates to something you have seen before.

Studies on creativity with engineers show that the ability to find not only creative but functional and working solutions for technical problems is equal to the ability to make abstractions. The better an engineer is at abstracting from a specific problem, the better and more pragmatic his solutions will be –even for the very problem he abstracted from (Gassmann and Zeschky, 2008, 103).

“The 5 Elements of Effective Thinking”, the mathematicians Edward B. Burger and Michael Starbird collected different strategies to do that (2012)

Being truly open-minded means being open to views that go against what we believe.

Those who think of themselves as being open-minded are often even more prone to stick to their first understanding as they believe to be without natural prejudices and therefore don’t see the need to counter-balance them. If we think we can “hold back” an interpretation, we are fooling ourselves.

The RAF fell for a common error in thinking called survivorship bias (Taleb 2005). The other planes didn’t make it back because they were hit where they should have had extra protection, like the fuel tank. The returning planes could only show what was less relevant.

5. Share Your Insights

This is true for more than just students it is true for why anyone stops wanting to work. They can no longer find meaning in what they are doing, it isn’t aligned with their personal goals and they don’t have the ability to work when they want to work.

When even highly intelligent students fail in their studies, it’s most often because they cease to see the meaning in what they were supposed to learn (cf. Balduf 2009), are unable to make a connection to their personal goals (Glynn et al. 2009) or lack the ability to control their own studies autonomously and on their own terms (Reeve and Jan, 2006; Reeve, 2009).

People are really bad at giving estimates.

Again: They were free to give any answer. But, sure enough, only 45% managed to get their papers done within the time they were sure they had a 99% likelihood to finish it under any condition they regarded as possible (Buehler, Griffin, and Ross 1995).

But there is one consolation: It has nothing to do with being a student. It has something to do with being human. Even the people who study this phenomenon, which is called the overconfidence bias, admit that they too fall for it (Kahneman 2013, 245ff).

According to the famous law of Parkinson, every kind of work tends to fill the time we set aside for it, like air fills every corner of a room (Parkinson 1957).

If you are afraid of cutting out words you have written you can move them to another document instead of deleting them. This way your writing becomes more concise and you don’t lose out on what you have written.

Of course, the chances that you actually go back to this document are quite small but it helps get over that barrier of deleting things.

6. Make It a Habit

We have the best chance to change our behavior over the long term if we start with a realistic idea about the difficulties of behavioral change (Dean 2013). And that is not so easy, because the more we are used to doing something in a particular way, the more in control we feel about it, even though we are less in control of it.

The more ingrained our routines are the harder they are to change. This is often why people stay in dead-end jobs because they are afraid of changing their routines.

The more pressure we feel, the more we tend to stick to our old routines – even when these routines caused the problems and the stress in the first place. This is known as the Tunnel Vision Effect (Mullainathan and Shafir 2013). But Mullainathan and Shafir, who examined this phenomenon thoroughly, also found a way out of it: Change is possible when the solution appears to be simple.

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