The word creativity comes from the Latin 'creare'---to make. In its simplest form, creativity is merely this, the act of creation. But when we speak of creativity, we are usually not interested in mundane creation: compiling data into a spreadsheet for example, or building a house from a plan. We are typically interested in a special kind of creation. The creation of something new in some indefinable way. Solving a problem in a novel or surpising fashion. Predicting a future no one else can recognise. Seeing something others cannot see and bringing it to life.
Defining this kind of creativity is a complicated thing. But we can grip our hands more firmly on one core feature---the generation of 'insight' or 'intuition'. Intuitive insight, in the sciences of the mind, refers to what we might call the 'aha' or 'lightbulb' moment. It can be distinguished from more analytic thought, like coming to a conclusion when working through a difficult mathematics problem, or figuring out how to traverse the London subway system. Analytic insight is the kind of insight that comes from trudging through information, step by step. Intuitive insight is instead the kind of knowledge that comes spontaneously, as if from nowhere: a new and urgent unforseen awareness.
Often, such insight comes when we're not expecting it, like the solution to an unrelated problem dawning when in the shower or washing dishes. Sometimes, it comes in the midst of a struggle to understand---confused by the teacher until a specific word or idea comes into mind and the insight comes all at once, as if it were hidden somewhere. These features of intuitive insight are the clue to its origins.
The anatomy of a lack of insight
Our brain is comprised of two kinds of cells: grey matter and white matter. Grey matter refers to our neurons: the basic signalling unit of the brain. Each neuron is connected to nearby neurons and passes electrical and chemical signals to these neighbours. These chains of interconnected signalling devices make up a complex series of'pathways' for information about the world to travel, and in this way neurons pass information about our perceptions to our muscles so that we can make the appropriate responses.
This is the role of all nerve cells, in all animals. In the jellyfish, in our spine, or in our brains, nerve cells are responsible for mapping some particular combination of inputs (sights, smells, familiar ways of moving our bodies) with some particular combination of outputs (a habitual way of responding to the world). This is the ancient autopoieitic function for which the nervous structures came about.
Some of these pathways are handed to us by evolution, but many more are developed by us over time. Certain combinations of inputs (sights, smells, familiar ways of moving our bodies) will develop neural pathways to combinations of output (habitual ways of responding to the world). In this way, our brain begins to create patterns that reflect the statistical structure of the world. Regions of the brain that respond to things in the world---things we regularly sense---become linked to regions of the brain that tell us what can be done about those things---how to feel about them and how to respond to them.
White matter refers to the other kinds of brain cells---glial cells. White matter fits all around the neurons (the 'grey matter') and takes care of them---protecting them, repairing them, and improving their performance. Importantly, the more you practice something---a particular pathway of input to output---the more white matter will grow around those pathways---all the better to support them in doing this thing that we do all the time. This is wonderful for speed and performance. But it means that these neurons, now surrounded by all this construction, can't change their connections very easily anymore. It means these neurons are quicker at doing some things, but much less good at doing others. The patterns in our brains become increasingly rigid.
How intuitive insight comes about
Many domains of psychology consider effective problem solving a case of putting together 'chunks' of information into the correct sequence, from the older information processing and gestalt approaches to more recent computational theories (a more comprehensive treatment here.
For example, gestalt theories believe humans interpret the world as some combination of patterns---gestalts---rather than perceiving every individual thing. A tree is not 'green' and 'leafy' but a tree, until we look closer. Problem solving on this view is an attempt to decompose, recompose, and combine these 'chunks' of information in our minds until we can create some kind of representation of the goal state. If the tree is overhanging the path, we must decompose the 'gestalt' of the tree into it's branches, and imagine the result of the offending branches being removed. Combined with gestalts of sawing wood and the compost heap, we have now a goal state in mind. Problem solved. A trivial example, but you roughly get the point.
Or, for something more recent, we might take the notion of 'Attentional Episodes'. In a similar manner as gestalt theories, problem solving is imagined as the effective sequencing of chunks. This time, the chunks are sequences of attention and behaviour. To eat, we must first attend to and recognise the food, then we must reach with the arm, then grasp with the hand, then put the hand to the mouth. With these 'episodes' sequenced thus, we can now eat the food. Problem solved.
These 'chunks' of information, and their sequences, can be mapped to our neural patterns---brain regions that represent the information and the pathways which connect them. But, because these patterns become increasingly rigid with time, we are most often drawn to the familiar sequences.
Intuitive insight occurs when we are able to move beyond these familiar patterns and discover new ones. In the brain, 'aha' moments are characterised by neural processes that are more diffuse---less associated with clear or typical patterns of behaviour or neural activity, or more open to different possibilities and patterns than those more readily available to us.
On the gestalt account, insight comes when we discover new ways of (re)combining 'chunks', or new kinds of goal states. Perhaps we can move the path instead of addressing the tree. Or instead of cutting branches, we can simply remove the leaves. Or perhaps we discover the notion of a 'jungle garden', and a myrid of new goal states in which overgrown can be desireable become available to us. Here, we experience a sense of unexpected satisfaction. Cutting the branch was the analytical solution. These new and different 'chunks' and 'goals' are the insightful one.
On the attentional account, insight comes from a slightly different place. To paraphrase myself:
We can note the similarities between different episodes or sequences and [abstract between them] ... For example, the episodes required to mount a bike are similar in many ways to those required to mount a horse. With experience of either, learning the sequence we do not know becomes much easier. Insight emerges when we recognise these new abstractions or are able to use old abstractions in new ways.
In whatever case, this is why intuitive insight feels so spontaneous. It is the unexpected combination of a pattern unfamiliar to the problem at hand with the problem, opening us up to the possibility of new 'chunks' of information, and new sequences of combination.
Accidental insight is the most reliable kind
There is an interesting note that sounds in the literature on psychopathology. Various troubles of the mind come with an unexpected gift---creativity. Bipolarity for example, and schizotypical inclinations. There's much speculation about why such a thing might be true. But given what we've learned here, one thing is obvious. During the manic episodes that characterise bipolar disorders, or the loose associative thought that characterises some schizotypy, familiar patterns of thinking and behaving are abandoned. Indeed, this is one of the reason such states of mind are thought of as 'disordered'. Intuitive insights come fast and often, it just so happens that perhaps not so many are particularly useful or appropriate.
In fact, many human traditions have sought to captialise on the fact that such randomness can inculcate intuition. Zen koans, shamanistic practices, and the widespread use of entheogens across time and place have all been used for precisely this reason. By inducing a break from the familiar, we can achieve new insights about the self, about the world around us, and about the nature of the divine.
More trivially, and perhaps less profoundly, this is precisely the reason that insight dawns so often while doing something quite unrelated to the problem we face. In the shower, or washing dishes. We have released ourselves from those sequences and chunks, those patterns of being in the world, that we are used to inhabiting for such a problem. In doing so, we open ourselves to new patterns, and in these new patterns we are liable to find something surprisingly apt.
And so, to best harness creativity, take a break. Do something different and activate different pathways. There are many kinds of intuitive insight, but the key to all is encouraging the happy mental accidents that come when we embrace the unfamiliar.