Are there absolute, eternal truths or is everything constantly changing? Plato believed there were pure, fixed, archetypal forms shaping the universe from within. Heraclitus, on the other hand, believed that the only constant was change. "We never step into the same river twice," he said.
Because Plato was so dogmatic, I have no hesitation in saying that he was wrong. We can't find a single thing that doesn't change. Scientific laws, religious beliefs, geological and biological structures, and personal habits are all fluid if we examine them closely enough, but Plato still has a point. Forms may not be eternal, but they may change so slowly as to be immutable for all practical purposes. Some things change easily, while some change barely at all, and some have more capacity for change than we think they do.
For example, it used to be part of scientific dogma that the structure of our brain cells, and therefore our consequent behaviour, was largely fixed by the time we reached adulthood. Brain cells can't regenerate themselves and they steadily die off as we age. Despite these constraints, we now know that the brain is far more "plastic" than we ever imagined. At any age and within days, a brain cell can establish thousands of new connections with its neighbours, changing its physical structure to do so, if given the right stimulation.
Because of this ability, we can learn. We are able to develop new ways of thinking and acting. We can draw on libraries of memory, learn from mistakes, think laterally, imagine the unknown and implement plans to achieve it. A wise old man has fewer neurons than a young man, but he has the potential for far greater connectivity and, thus, intelligence.
Neuroplasticity, this capacity of the brain to make new connections, has given a scientific rationale to the philosophy of Positive Thinking ('You can become the person you want to be. You can achieve anything you want. You can live a life beyond limits'). Yet if change is always possible and we know how it happens, why is it still so hard to achieve?
It is self evident that we can't just think or visualise our way to perfection. This is not the way the brain works. It also needs action and lots of it. I imagine that most of the billion overweight people on this planet would rather be thinner, but wishing or hoping doesn't make it happen. Our thoughts strut and bluster on the stage of consciousness, but in the end it is what we do that matters far more than what we think.
Change has to occur at the level of the neurons. To learn a new behaviour, dormant genes in the DNA of individual cells are woken from their slumber by a demand from the environment. If the matter seems urgent enough, these genes then "express" themselves by constructing hundreds of highly specific docking ports at the active signalling tips of their cells. These new structures amplify the flow of chemical and electrical information between any one cell and thousands of others, streamlining their effective group action. Only when these new connections are sufficiently strong and well practiced, can they override the older established patterns of behaviour. A single thought, or a weak thought many times, or a passionate thought without the reinforcement of action, just won't do it.
Any lasting change usually requires at least four elements: conscious thought + strong motivation + physical action + repetition. The only exception is what is called "one shot" or "traumatic" learning.
My neighbour's little white dog once got bailed up by a cat in a strange park. Six months later, back at the same park, he froze and refused to enter. That is "one shot" learning, souped up by strong "do not ever forget this" fear hormones. That dog learnt his defensive response without any need to repeat the experience, and it is probably embedded for life.
Twelve years ago I fell though a ceiling and made a neat three point landing on both feet and my bum. As I lay there in excruciating pain, I thought, "I've broken my back. I'll never walk again. What an idiot!", thereby adding emotional anguish to the physical damage. I was rushed off to Sir Charles Gairdner Hospital in Perth where I got superb care. (Thank you, Charlies. It seems that Tuesday morning is a good time to have an accident.) Fortunately I got off lightly. One foot was broken, but is now healed. The other seemed to be fine at the time, but is now dicey, and my back is okay so long as I don't stress it.
Because that event scared and shocked me, I wasn't going to forget it. I made a strong "beware!" resolution to avoid such accidents in the future. With that memory ever ready to flash into my mind, I now always get a tradesman to help me if there is the least possibility of danger, and I refuse to assist anyone else with their heavy lifting. I know too many people with irreparably damaged backs. I've been warned.
About the same time, my handyman uncle fell two feet from a ladder. He broke his elbow so badly it never repaired, and he went into serious decline thereafter. His fall and mine left me with an enduring mantra - "You can ruin your life in one careless moment" - and I became more conscious of potential accidents waiting to happen.
A year later I almost fell down a flight of stairs. I was carrying a box of books which had obscured my peripheral vision of the top step. "I'll have to be more careful", I thought, but a week later I almost did it again, also carrying a box of books.
This second stumble made me realise that the thought and the motivation alone were not sufficient if my mind was preoccupied with something else. I needed to change the way I habitually walked up or down stairs and do it frequently enough to establish a new pattern. As I said earlier, lasting change requires more than good intentions. It needs thought + motivation + action + repetition.
It is easy to walk up or down stairs safely. It takes only a rudimentary level of attention, but not less than that! When I was hurrying up or down stairs, I tended to be out of balance, falling forward on the next step, counting on my split-second responses to keep me upright. When I was relaxed and balanced, on the other hand, I used entirely different muscles in my legs and abdomen, and the movement felt smooth and comfortable. It was very different from a hurried, scrambling kind of way of stair-walking.
Because I knew that change had to be embedded at this kind of automatic "muscle memory" level, I decided I would try to walk in this relaxed fashion every time I came to a flight of stairs. Of course, I often failed. I would forget my good intentions until halfway down the stairs. When I forgot, I got annoyed. Because I got annoyed often enough, I started to remember. It took about a month before I was remembering more often than forgetting, and about a year, or approximately a thousand flights of stairs, to fully establish the pattern. It's not that I'm a slow learner. It really does take that long to overrule a habit and embed a new routine.
Persistence is the key - doing the same thing again and again and again. Each time we repeat a new task, the hippocampus, which is that part of the brain that consolidates memory, leaps into action. Circuits of electricity flow between those parts of the brain that plan and coordinate movement, and those parts of the body that enact the movement. The hippocampus knits this complex activity together into a unified template and stops it fading into oblivion, as it normally would. It takes the hippocampus about a year of repetition to fix a new action as a long-term skill or habit. Any less and the changes may not last.
Positive thinking promises the Earth but it has obvious shortcomings. It rarely produces results that live up to expectations. The problem is that thoughts are nowhere near as powerful as we assume them to be. They are more like wishes than orders, and whatever we aspire to is likely to change in the execution anyway.
There is no mystery about how positive change occurs. Our brains work according to the adage "actions speak louder than words". This means that lasting change doesn't come from imagining our goal. It comes from repeated activity towards that goal and the enthusiasm necessary to see it through.