What is a Structure?
Look around you. What do you see? Buildings, roads, hills, lakes, rivers, ocean, trees, people etc. Everything that you see at this moment, you expect to see after that blink of your eye. Our natural world (at least the one that surrounds us) does not change that fast. Not only that, you expect to see these things in roughly the same shape and form. That expectation of being there, in roughly the same shape and form remains there even beyond the duration of the blink of an eye - most of them will be there even tomorrow. Well, people may move, but they mostly continue to exist (on planet earth) for durations ranging from months, to years, to decades. Trees may grow, and unless something is done to them they tend to remain where they are for many decades. Others may continue to be there for centuries.
Let’s take buildings first - they tend to remain in their existing condition for decades if not centuries (with proper maintenance and no severe external forces). They tend to persist. Depending on their construct, tend to persist even in the face of negligence and severe environmental factors. Just think about buildings from history - the acropolis is more than two millennia old, the pyramids are many millennia old. And even if you look at archeological ruins, you have an example where severe negligence, vandalism and environmental factors may have brought devastation to them, but they tend to still hold some amount of resemblance of their original form. Buildings are are the most relatable examples of structures.
So, at least from that perspective we see structures as a fundamental building block of our world. Thus, in this post we want to take the time to examine structures. We want to review what structures are, take a look at some examples, look at different categories of structures, look at typical characteristics of structures, and examine what role they play in our world.
Definition of Structure
Wikipedia defines structure as:
A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized.
I will approach the definition of structure from a system design perspective:
A structure is a composition of elements in a system that make them interconnected in a way that the resulting subsystem tends to resist change. The resistance to change would be exhibited in both the change in its form as well as in the state of its existence.
This definition highlights two key attributes of a structure (to be elaborated later in the post):
Interconnected organization of elements
Resistance to change. This shows up in two different formats:
Resistance to destruction - the resulting property is called “persistence”.
Resistance to internal change - we may perhaps call this “rigidity"
The elements of the structure always tend to have forces moving in opposite directions resulting in an ever-existent tension. This is a balance that maintains the structure in place.
This resistance to change tends to allow structures to have an outsized impact on the super-system. While non-structural elements in the super-system tend to move about freely, their freedom of movement will be constrained around the structure.
Sometimes, forces (external or internal) to the structure become sufficiently high to disturb this balance, resulting a dramatic collapse of the structure. “Dramatic collapses” are another hallmark of structures.
Examples of Structures
I’m starting off with some more straightforward examples of structures, obviously going in an increasing order of level of complexity:
A building - Think about the steel framing, the concrete reinforcement
A diamond - Think about the atomic structure of diamond. Each carbon atom is strongly bonded to four adjacent carbon atoms located at the apices of a tetrahedron (a three-sided pyramid)
The DNA - Think about the double-helix structure
An atom - Think about how the electrons go around the nucleus
The human skeleton - Think about the bones connecting to one another, giving our bodies the structural form
A corporation - Think about the human resource structure of a corporation - the CEO at the top, senior management reporting to the CEO, mid-management reporting to the senior management, lower-level employees reporting to the mid-level managers
Types of Structures
Structures may be characterized in various ways depending upon variances of some of its attributes. Here are some examples to start with:
Static structures vs. Dynamic structures
This categorization is based on the level of dynamism of in a structure. Static structures don’t change - they tend to be rigid. One the other hand dynamic structures change in certain ways, while resisting change in other ways. A steel and concrete building may be considered a static structure, while the body of an airplane may be considered somewhat dynamic structure - the wings tend to curve in flight for better flight aerodynamics, and the fuselage tends to compress and expand depending upon the difference better the atmospheric pressure outside the fuselage and inside it.
Man-made structures vs. Natural structures
This categorization is based on origin - a snowflake is a natural structure, but a silicon chip is a man-made structure.
Physical structures vs. Information structures
This one will need more explaining, and will need to be taken outside the scope of this post - but let me try. Physical structures are easy to understand - anything that has a physical presence - a building, a diamond etc. Information structure is a structure that is purely based on information - our knowledge, belief systems, value systems, legal systems etc. Let me give an example - what stops most people from picking up a product from a store and just leave without paying (even if the store may not have an exit check)? There is no wall that stops the product from leaving the store. But still most people don’t do it. That is because of what I define as “information structure”.
Characteristics of a Structure
Persistence - This defines how long a structure tends to exist on the average
Rigidity - This defines how much the structure resists internal change
Dramatic collapse - Due to the rigid nature of structures, they tend to resist change to a certain point of external pressure, and then collapse (in dramatic fashion) beyond a certain point
Dynamism - This is the opposite of rigidity - amount of change a structure tends to undergo.
Attributes of Structure
Rate of Change
Extent of Change possible without collapse
Role that a structure plays
I am going to define the role that structures play in the context of the Inceptone System Design Framework (more to come on this).
Structures play a very important role in our world - everything that you see, feel and know of that persists over time is essentially a structure. But, a better way to look at it is - everything that persists have a structuredness property. Structuredness tends to be higher in those that persists longer, and lesser in those that persist for shorter duration of time.
Had we been non-intelligent beings, that would have been it. But we being intelligent, we are capable of processing information. And that result in the creation of structure of a very different kind - that is way more powerful - is not visible, but is ever-present - I call it the information structure. Information structures have shaped human civilization from its early days - in fact the formation of civilization would not have been possible without the existence of “information structures”. And for ongoing progress and development of our civilization, we need ensure we have better understanding of information structures, so that we can better use them to build and maintain better systems.
© Copyright - Sid Barthakur, Inceptone Inc.