I’m in the middle of reading Flow, by Mihály Csíkszentmihályi, and so far, I love it. It describes the “flow state” of consciousness, that state of “everything is irrelevant except for the task at hand” in which time flies past without your noticing, and you don’t notice hunger or thirst or people moving around you. Flow can be induced when performing a difficult task which lies within your abilities, where immediate feedback is provided. I, at least, feel characteristically exhausted after coming out of a long period of flow - but it’s a good kind of mental exhaustion, much as the tiredness after a long swim is a good kind of physical exhaustion (in contrast to tiredness-after-a-long-day-of-doing-nothing, which feels sort of lazier and unwholesome). The Wikipedia page is a good enough explanation of flow that I will not describe it further here.
I myself have experienced flow when playing violin in the orchestra, playing the piano solo, playing chess, doing maths, doing sudoku-type puzzles, reading (fiction and non-fiction), doing exams, and programming. These are the examples that come to mind during five minutes’ probing of my mind - there may very well be more.
I never experienced flow during a music exam (unfortunately) - this is probably because during an exam, good results are required, and this creates a lot of pressure to perform well. As an added source of worry during music exams, you are performing alone, doing something where it is excruciatingly obvious when you get it wrong. If the pressure to do well is too great, it is very hard to achieve flow; Csíkszentmihályi would claim that this is because “the self, in the form of worry and fear, is too strongly asserted when under pressure, and flow requires losing the sense of self”. I hold this to be a fringe benefit to the modular system of exams - if you mess up one module, it’s not the end of the world.
I no longer experience flow during chess, because I have had several years of hiatus since being fairly good at chess - time enough to forget many of the patterns that I used to be able to see effortlessly - and so the game has become a little too difficult for me to attain flow. However, now that I am playing casually again, I hope that it might become easier to achieve flow during chess. Maths is the main source of flow in my life at the moment. I measure how long I have spent doing a particular problem by how many sheets of paper I have used, and I always end up having used far more sheets that I feel there could possibly have been time for. I also notice flow-tiredness pretty often after doing a long bout of maths, which is a fair indication that I have been in flow. It is from maths that I have come to think that I can kick flow up a notch if required, because I can sit a maths exam, completing (to a better standard than normal) questions that feel harder than those I do for practice, and come out of the exam absolutely exhausted - with flow-tiredness times two. However, the experience feels much the same as “normal flow” at the time - that is, it doesn’t really feel like anything, and the problem I’m solving is all there is. It’s quite hard to perform accurate introspection on a state of mind in which introspection is entirely halted! I have to rely on evidence from outside the experience: the fact that I am much more tired and have completed more than I would have done in “normal flow”. I would be interested to know if anyone else has what they perceive to be two levels of flow. As further evidence in favour of “multiple levels of flow”, it is apparently possible for groups to achieve flow together, working on the same task - I struggle to come up with an activity in which the delay of talking is not a huge barrier to flow. (I suppose that if a group can get to the stage where its members are passing around information before it is requested, by anticipating the questions, then it could be possible.) It seems much more likely that a “lesser level” of flow could be achieved in a group, during which interruptions are not so disruptive; I cannot imagine my maths-flow or anything like it surviving with people’s talking around me and my having to reply (with anything more sophisticated than “mmm”).
I go into flow with maths exams (A-level, BMO, Tripos, and the corresponding mock exams), but also in certain other subjects. When writing an essay for my A-level Latin exam, I went into flow. Interestingly, I never went into flow when writing practice essays for Latin - it took the structure and importance of the actual exam to get me into flow. I’m looking for ways to get more flow; I remember that I used to go into flow all the time when I was younger, through doing sudoku and related puzzles, so this is perhaps an avenue of exploration.
I like the contrast that Csíkszentmihályi gives between “pleasure” and “enjoyment”. “Pleasure” is your standard run-of-the-mill emotion, something that hasn’t got a strong thought component involved. It is (of course) not a bad thing, but it is somehow less wholesome than “enjoyment”, which is the pleasure obtained from investing a large amount of mental energy in something. Watching television is usually pleasurable (assuming it isn’t boring, anyway), while reading a really good book is enjoyable - possibly because of the work involved in constructing a mental model, which elevates the act of reading from “pleasure” to “enjoyment”. Thinking on the distinction, I realised that in fact most of the things I do as a distraction are not enjoyable, and many are not even pleasurable - forthwith, I am deleting almost all the iOS games I have on my iPod, because their only purpose (from my perspective) is to be used as a time-sink, rather than to provide pleasure. I might take up crosswords again - while not necessarily an easy flow-inducing task (because the crossword is split up into many small but very difficult tasks, rather than small and reasonable ones), it is at least enjoyable.
The book Flow describes many different activities that can induce flow in a skilled practitioner - rock climbing, ice skating, even assembly-line work - so it is not a phenomenon that is confined to mental pursuits. (The skew of this blog post is just because I have never achieved proficiency in any physical activity.) I would be interested to know what activities induce flow in my readers.