The history of information technologies can be looked at as a punctuated increase in degrees of freedom.

Removing a dependency opens up new possibilities. A freedom from is also a freedom for.

This is the fourth essay in the Autonomy and Cohesion series. The first one was about the basics of the balance, why it is important, where it works and how. The second was about the forces that bring cohesion and the tools that we use to keep things connected and in sync. The third essay introduced the spectrum of cohesion, differentiating five zones depending on how cohesion is achieved. The next post of the series will take a closer look at cohesion technologies used in the fifth zone, Interoperability. Before that, and to prepare the ground, this essay will focus on another curious phenomenon: the balance is somehow present, in a more primitive, mechanistic way, in the tools that we use. And it enables and is enabled by the autonomy and cohesion forces in the larger socio-technical system.

When it comes to tools and technologies, it won’t be appropriate to use autonomy (with a few exceptions). Instead, we can talk about freedom and decoupling.

Let’s go!

When a rusty screw is stuck

There is a maintenance philosophy attributed to Earl Dibbles Jr., according to which,

you only need two tools in life: WD-40 and duct tape. If it doesn’t move and it should, use WD-40. If it moves and it shouldn’t, use duct tape.

While I’m sure you have used duct tape, WD-40® might not be known to everyone. So, what is it? WD-40® is a widely used penetrating oil, and since its invention in 1953, it has indeed penetrated every corner of the world. It can be found in every hardware store, sailing boat, car repair shop, and many households. WD-40® is a lubricant, rust preventer and remover, and moisture displacer. According to the company website, it’s much more than that, so it lists 2000 uses. But if we come back to the wisdom of Earl Dibbles Jr., you use it when something “doesn’t move and it should.” It won’t help for a dead cat or a frozen progress bar on your screen, but for just about anything else, it should. Especially for a machine part that is stuck. Like a rusty screw. You spray a bit of WD-40®, and the screw is free again. You can unscrew it.

Degrees of freedom

The freedom of movement in space can be quantified. According to classical mechanics, rigid bodies have six degrees of freedom in three dimensions. They can translate (move forward and backward, up and down, left and right) in each of the three axes and rotate in each of the three axes. When classical mechanics came up with this theory, sailors had already established terms for each degree for centuries: surging, heaving, swaying, rolling, pitching, and yawing.

If you take a rigid body, say a rod, cut it in two pieces and then connect the parts with a joint, this system of bodies, called a kinematic chain, will have a degree of freedom equal to the combined degrees of freedom of the parts and the joint. If the joint works like a hedge, such a kinematic chain will have 7 degrees of freedom. Cylindrical joints can have two degrees of freedom: sliding and rotation. A robot’s arm with such a joint will have 8 degrees of freedom. In 2007, Dean Kamen presented a prosthetic arm with 14 degrees of freedom,¹The human arm has 7 degrees of freedom, but together with the shoulder and the hand, 21. and a decade later, another DARPA-financed program developed a modular Modular Prosthetic Limb (MPL) with 26 degrees of freedom.²Perry, B. N., Moran, C. W., Armiger, R. S., Pasquina, P. F., Vandersea, J. W., & Tsao, J. W. (2018). Initial Clinical Evaluation of the Modular Prosthetic Limb. Frontiers in Neurology, 9, 153. https://doi.org/10.3389/fneur.2018.00153

The concept of degrees of freedom is used beyond classical mechanics and robotics. In statistical mechanics, for example, it is applied to the movement of particles and is correlated with energy. A system with more degrees of freedom can carry more energy.³According to the equipartition theorem.

Degrees of freedom can be positively correlated to variety. Large structures expand and contract due to temperature changes. Flexible expansion joints in bridges give more degrees of freedom and, respectively, higher variety to respond to changes in the environment. Yet sometimes, more degrees of freedom do not bring more variety. My Sneekermeer sailing boat has a folding mast so it can go under bridges. It has more degrees of freedom than the masts of most sailing boats. And when it comes to going under bridges, if we apply Ashby’s law, it also has more variety. But in other situations, it has less variety than comparable⁴In relation to the degree of freedom given by the hinge, mast can be approximated to rigid bodies. Otherwise, they are not, and their ability to bend plays an important role in sailing performance. By comparable, what is meant here is that they are of the same material and height and are used in the same kind of boats. But importantly, a comparable fixed mast should be deck-stepped and not keel-stepped. On the other hand, the fact that foldable masts cannot be keel-stepped brings their overall variety down since they cannot be used on large cruising yachts where high compressive stresses occur. fixed masts. In heavy weather, the lower variety is due exactly to the hinge that gives that extra degree of freedom.

Back to our rusty screw. It’s stuck. It has no degrees of freedom. Spraying with WD-40® will free it. We can unscrew it. And when we do, it both rotates and translates (comes up). This means it should have two degrees of freedom. It has only one. Its rotation and translation are tightly coupled.

Coupling removes degrees of freedom.

Decoupling

The history of information technologies can be seen as a punctuated increase in the degrees of freedom — a history of decoupling. Content decouples from medium, representations decouple from mirroring reality, software decouples from hardware, interfaces decouple from infrastructure, data decouples from applications, and content decouples from the host.

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