Over the last several decades, research discovered the duality of the mind. One part, initially called the right brain because the functions appeared to reside in the brain's right hemisphere, controls visual thinking and pattern recognition. The other hemisphere, the left brain, controls verbal and linear thinking. Many other mental functions seemed to have a preferred hemisphere: analysis, left brain; intuition, right brain; orderly processes, left; random processes, right. Thought undertaken by the left brain tends to be more practical, serious, structured and judgmental while on the right thoughts are more emotional, playful, flexible and nonjudgmental. Left-brain-dominated people turn to professions such as engineering, accounting and the law, while right-brain people are more often writers, musicians and artists.
The education system throughout most of the Twentieth Century has focused on the development of the left brain functions. However, for creative thinking and problem solving, the optimum thinking mode employs both hemispheres working in a dynamic balance.
One device that can be used to enhance and balance the thinking process appears to speak to both sides of the brain: the metaphor. The metaphor consists of word images connecting an idea to something it cannot be. It allows us to replace one kind of thought with another, usually one which is more familiar. Metaphors are mental maps which make complex ideas easier to understand. Metaphors synthesize disparate ideas in the right brain; they allude, match and compare. They include possibilities that sequential thinking in the linear functions of the left brain exclude.
According to Gabiele Lusser Rico, metaphors "create tension and excitement by producing new connections and in so doing reveal a truth about the world we had not previously recognized." They diverge rather than converge and not only can place the familiar in a context of the strange, but also can place the strange in a context of the familiar. That is, metaphors make the complex simple, but may also make the simple complex.
The richness of metaphors fill our language: roads have shoulders; ideas are half-baked; cities have hearts. Metaphors jump to mind to explain scientific concepts that would be incomprehensible to the layperson. William Harvey described the heart as a pump; Niels Bohr described the atom as a tiny solar system with the nucleus in the centre and the electrons orbiting like planets around it. The concept of weather fronts came from the mind of Vilhelm Bjerknes who saw the conflicting interactions between warm and cold air masses as similar to the European battle fronts of World War I.
Metaphors may be very pedestrian or cliched or may miraculously conjure unexpected images of astounding insight. The chemist Friedrich von Kekule spend long hours of research trying to understand the structure of a certain class of organic molecules such as benzene. One night, on a dream, he saw snakes chained in a ring, each with the tail of another in its mouth. Upon waking, he realized that the structure of the benzene molecule was a ring. This metaphoric insight revolutionized organic chemistry.
The metaphor can transform entire families of problems into other realms where we can apply already developed skills toward solutions. It's the case of not seeing the forest for the trees. Metaphors move us a distance away from the situation so that we can better see an avenue for solution.
How strong are metaphors in teaching? Most good teachers will develop vivid and powerful metaphors for introducing students to a new field of knowledge. Such metaphors conjure a sensual image of the new concept by bridging the new knowledge to past ideas, images and experiences already safely stored in the brain. It is no wonder that advertising seeks to build the most powerful metaphors available, for example, linking the driving of a car to freedom and open spaces or to sexual encounters.
Ordinary conversation relies strongly on metaphors. They are essential to everyday speech because they are able to make multiple connections among ideas and therefore communicate complex and detailed information in a brief phrase or two.
Metaphors expand the mind because they are able to link a concept to familiar patterns gathered through a lifetime of experience. They are tools that offer great assistance to lifelong learning since the longer we have lived, the more experiences are already wired into our brain. However, one the other side of life, metaphors can also be powerful tools for teaching children and expanding their horizons. I am sure that most of us have been asked a question by a small child and used a metaphor to answer. What was that loud noise outside? That was thunder, it is the sound: of two clouds crashing together; of God clapping.
If you wish to teach, work on your metaphors. If you wish to learn, find the proper metaphor to imprint new knowledge in your mind. What is Life? Life, my friend, is like...