Source: 📖 How to Take Smart Notes ch.9
The Ziegarnik Effect can be circumvented by simply writing down unfinished tasks in a manner that convinces us they will be taken care of. This allows our minds to let go of them to focus on something else, trusting that they will emerge once again when needed.
Conversely, one can leverage the Ziegarnik effect by keeping unanswered questions and problems floating in our minds while doing another more cognitively relaxing task—going for a walk, taking a shower, listening to music. This allows our brains to work on problems in the background, in a broader, more softly-focused way which is great for connecting different ideas and lines of thought internally. This is why we often find solutions to problems in rather unexpected, casual situations.
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