All martial arts are about action. They are about crystallising sensory input, consciousness and physical dexterity.
All actions start with a thought. A single decision must be made before we can move. That decision is "it's time to move".
In 2008, the Max Planck Institute in Leipzig published their research into the relationship between thoughts and actions. Basically, they set up experiments where they could measure the brain activity of a person who was conducting physical activity. Their brain signals were monitored and timed.
In the study, published in Nature Neuroscience, participants could decide if they wanted to press a button with their left or right hand. They were free to make this decision whenever they wanted, but had to remember at which time they felt they had made up their mind. The aim of the experiment was to find out what happens to the brain in the period just before the person felt the decision was made.
What they discovered was quite amazing. It seems that before we make a "conscious" decision to do something, our unconscious mind is already preparing us for movement. Scientists have surmised that this would prevent our conscious minds being clogged with the many thousands of minor decisions that make up our day.
So what relevance does this have to martial arts? There are practitioners who seem to move like lightning, and with reflexes that are simply amazing. This is no accident, and does not come from building big muscles and heavy exercises. Sharpness comes through repetition. Even slow training like Tai Chi will eventually increase speed of reflexes, as the memory of the movement helps the unconscious mind to prepare for movement in detail.
From a philosophical standpoint, the Buddhist saying is "a journey of a thousand miles starts with a single step."
...Only we now know that even before we decided to take that single step, our unconscious mind had made that decision for us.
... Or perhaps, the single step is an unconscious thought that we have yet to perceive.
Either way, as we struggle to make the right decisions, perhaps the answers are there already. We just have to find a way listen to our unconscious mind.