Mental indexability relates to creating software or structures that matches how you index or group stuff in your mind. One can increase it by either making the software better fit how you think about it, or changing the way you think about the software. For example, how do you turn a mental query such as, "Where is the code that calculates the taxes?" into keystrokes to locate such code in the file system or code repository. This also helps with impact estimates. If you know how code is divided and categorized, then you can use the mental model to estimate impact without actually performing the actual steps. See also FourLevelsOfCompetence ''I think this is very important, as one of the limitations of the human mind seems to me to be the limited number of pointers to data we can retain, while holding onto information for many years. I am 60 this month. I can still recall at will the phone number of the home I lived in up to 1961, which was important then but irrelevant now. Some of the things I need to recall now are how to do computing tasks which occur every few months and have slid to the back of my mind.'' -- JohnFletcher I agree that this is an important observation. My brain (and probably everyone's) works best if it works with structures instead of lots of (unconnected) facts. An example: I recently had to look up the address of a holiday location I had been to last year. I didn't memorize it, but I was able to find the town by locating it with GoogleMaps (following streets we travelled). Enter town, street and some keywords and voilĂ  you have got the address. This is the interesting thing about the internet and search engines. All you need is the structure - what is connected to what in which ways - and it will provide you with the facts. Only problem: Where do you get the structure from? You need to play with the facts initially. See YouCantLearnSomethingUntilYouAlreadyAlmostKnowIt. -- GunnarZarncke ''I am not sure why this is being called a "structure" above. Google is generally a keyword (text) search.'' Hmm. It's the amount of "structure", i.e. the measure of interconnectedness of the memorized information. It's a range with nearly unconnected "facts" at one end and highly connected general knowledge at the other end. Rote memoization of historical dates, telephone numbers/addresses etc. usually count as examples of the first one, though historical dates can be highly meshed with the historical era, its rulers and their actions, but this mostly happens only if we develop a deeper interest. This leads to the other end. If more and more pieces of information are put into relation and we find more and more patterns, complex structures develop. At some point, these structures become so intricate and support their parts so well that the original facts fall out as special cases and need no longer be memorized at all so to say. In this lingo, my example was intended to show that I had structures for * general geographical relation and connections (the geographical location of the region and larger towns there) * concrete location of the streets we traveled and their connection (this '''is''' special data that must be memorized for the scheme to work, but it is easy due to holiday delight) * ability to access and use an atlas (in this case, GoogleMaps) * linguistic ability to describe the holiday location with key words * ability to access and use a search engine (in this case, google) These together allowed me to dispense with memorizing the address (including town name) and phone number of that location. -- .gz ''I believe there is a cognitive psychology term known as "chunking". Perhaps "chunks" are what you have in mind, or related to what you mean, when you say "structures"? -- ElizabethWiethoff'' Hmm. From http://en.wikipedia.org/wiki/Chunking_(psychology) I get, that this is related, but not quite what I meant. Chunking is about short-term memory, whereas I spoke about long-term memory - after all, the trip is months away. But maybe the same principles are at work? -- .gz [Much later] I heard it said that people in developed countries become so used to 'mental help technology' (aka PDA, PCs, WWW) that they more and more lose the ability to memorize facts. The memory simply isn't trained any more. And maybe the brain adjusts. Many people have difficulty to remember even (?) their own phone number - because they do not need to, having structures to recover it if need be. -- .gz ''Interesting. Just yesterday, I could not remember my home phone number. As I explained to the person I was speaking to, how often do I have to ring myself at home? However, I did remember my mobile number.'' -- DaveVoorhis I sometimes tell the other party, "I don't call myself very often because I'm boring to chat with." I believe your account is becomming more common as we use phones less. -t ---- See also: WherePsychologyMatters, WhatIsModularity ------ CategoryMind, CategoryPsychology, CategoryLearningMethods