I thought I would share my little thought experiment to explain why I believe that chi is efficiency and not energy. To do this I'm going to use my robotics framework, and the scientific mechanism of describing a simplified model of the real world in order to aid understanding. So, consider this little diagram below:

This picture represents a 2D model of Tai Chi, and chi. What we have is a little robot (as an approximation to a human) standing on the ground and pushing against a spring. This robot has four different joints connected together by linkages, and the question is how much force can this little robot issue into the spring? We also assume that this that there is infinite friction between the robot's "foot" and the ground, to remove any complications to do with grip (or rooting).

In this diagram I also represents the concept of total (scientific) energy available, as the big bucket filled with water. Humans have only a finite amount of chemical energy available to them that they can transform into muscular force. This is the classical scientific view of energy, which can transform stored chemical energy (glucose) into a force on the spring (pressure). To model this transformation, connected to this bucket are a series of hosepipes and taps that go to each of the joints, so that the joints of the robot are controlled by hydraulics. The question now is how do I distribute the total amount of hydraulic pressure available across the different joints in order to achieve the maximum force into the spring? This can be solved mathematically (which I leave as an exercise for the reader :-). Intuitively however it is likely that the optimal structure is, an arrangement whereby the linkages of the robot form a classic arch, just as has been used for thousands of years in civil engineering.

To my mind therefore doing Tai Chi is akin to solving this problem. If we can distribute our available glucose energy throughout the joints of the body optimally, that will be the maximum force we can issue. How much chi we have therefore is equivalent to how optimally we transfer force across the joints of the body. This is commonly referred to as maintaining "your structure", "correct body alignment" and "whole body coordination". The better we are at utilising every possible joint and muscle, the more effective we will be at issuing force. Chi is therefore a measure of how efficient and effective we are at solving this complex optimisation problem instinctively. No one actually solves a complex optimisation problem mathematically in real-time of course, what we do is use the feelings and sensations from within our own body to "just do it". In Chinese parlance we call these sensations "feeling that chi".

The alternative, and in fact mainstream, view of chi, is that it is a mystical energy force which I represent in the following diagram:

This diagram assumes that there is an additional chi energy that we can use to add force to the spring. This chi energy does not conform to the most fundamental physical laws in science: the conservation of energy. If it did, it would go into the original bucket. I do not believe this can possibly be true, as this would represent the most profound and fundamental revolution of our entire scientific knowledge base. Amazing claims require amazing proof, and there is no amazing proof. Frankly there isn't even any weak and feeble proof. Unfortunately however it is impossible to prove a negative, so you cannot prove that the second model is incorrect, but I defer to Occam's Razor :-)

I do believe that the concept of "chi" is useful. It is a powerful way to visualise how things feel inside the body. All we have are feelings and it is perfectly valid to feel as if chi is flowing, even if it doesn't exist. After all, we are happy to visualise things like "extending our roots into the ground like a tree", but no one in their right mind would claim that we actually have roots, and understand it is just a metaphor. Chi is an incredibly powerful visualisation metaphor, and mastering these feelings of chi is fundamental to achieving mastery of the internal arts. It is of course important to realise that there is a distinction between how things feel and how things are. Chi is not energy it is a feeling.

This picture represents a 2D model of Tai Chi, and chi. What we have is a little robot (as an approximation to a human) standing on the ground and pushing against a spring. This robot has four different joints connected together by linkages, and the question is how much force can this little robot issue into the spring? We also assume that this that there is infinite friction between the robot's "foot" and the ground, to remove any complications to do with grip (or rooting).

In this diagram I also represents the concept of total (scientific) energy available, as the big bucket filled with water. Humans have only a finite amount of chemical energy available to them that they can transform into muscular force. This is the classical scientific view of energy, which can transform stored chemical energy (glucose) into a force on the spring (pressure). To model this transformation, connected to this bucket are a series of hosepipes and taps that go to each of the joints, so that the joints of the robot are controlled by hydraulics. The question now is how do I distribute the total amount of hydraulic pressure available across the different joints in order to achieve the maximum force into the spring? This can be solved mathematically (which I leave as an exercise for the reader :-). Intuitively however it is likely that the optimal structure is, an arrangement whereby the linkages of the robot form a classic arch, just as has been used for thousands of years in civil engineering.

To my mind therefore doing Tai Chi is akin to solving this problem. If we can distribute our available glucose energy throughout the joints of the body optimally, that will be the maximum force we can issue. How much chi we have therefore is equivalent to how optimally we transfer force across the joints of the body. This is commonly referred to as maintaining "your structure", "correct body alignment" and "whole body coordination". The better we are at utilising every possible joint and muscle, the more effective we will be at issuing force. Chi is therefore a measure of how efficient and effective we are at solving this complex optimisation problem instinctively. No one actually solves a complex optimisation problem mathematically in real-time of course, what we do is use the feelings and sensations from within our own body to "just do it". In Chinese parlance we call these sensations "feeling that chi".

The alternative, and in fact mainstream, view of chi, is that it is a mystical energy force which I represent in the following diagram:

This diagram assumes that there is an additional chi energy that we can use to add force to the spring. This chi energy does not conform to the most fundamental physical laws in science: the conservation of energy. If it did, it would go into the original bucket. I do not believe this can possibly be true, as this would represent the most profound and fundamental revolution of our entire scientific knowledge base. Amazing claims require amazing proof, and there is no amazing proof. Frankly there isn't even any weak and feeble proof. Unfortunately however it is impossible to prove a negative, so you cannot prove that the second model is incorrect, but I defer to Occam's Razor :-)

I do believe that the concept of "chi" is useful. It is a powerful way to visualise how things feel inside the body. All we have are feelings and it is perfectly valid to feel as if chi is flowing, even if it doesn't exist. After all, we are happy to visualise things like "extending our roots into the ground like a tree", but no one in their right mind would claim that we actually have roots, and understand it is just a metaphor. Chi is an incredibly powerful visualisation metaphor, and mastering these feelings of chi is fundamental to achieving mastery of the internal arts. It is of course important to realise that there is a distinction between how things feel and how things are. Chi is not energy it is a feeling.