We humans are extraordinarily complex, shaped by billions of years of evolution. Understanding human systems is challenging because they differ from natural or technical systems. Thinkers such as Ralph Stacey and Dave Snowden have developed methods to make sense of this complexity, highlighting how human interactions shape unpredictable and adaptive social systems.
Humans are complex
Our human bodies
are extraordinarily complex systems that have evolved from stardust since the universe sprang into existence in the Big Bang around 13.7 billion years ago, and since life first emerged on Earth at least 3.5 billion years ago.
There are about 200 different types of cells in the human body, and over 37 trillion cells.
The human brain is the most complex system in the known universe. It is a highly connected structure. Estimates vary
, but the human brain is estimated to have approximately 86 billion neurons.
This size compares to the latest estimates for the number of stars in the Milky Way, somewhere between 200 and 400 billion.
In turn, each neuron in the brain may be connected to up to 10,000 other neurons, passing signals to each other via as many as 100 trillion synaptic connections.
We learn nothing about love, anger, or jealousy by studying the individual cells in the human body, the neurons, and the brain’s synaptic connections.
These are emergent properties of an enormously complex system.
We are highly complex, volatile, unpredictable, emotional, and frequently irrational creatures laden with cognitive biases.
Human systems are complex
Human systems are different from natural, biological, or technical systems. We are not like birds, termites, or computers.
Over the past decade, several individuals have developed innovative approaches to understanding human interaction and systems.
Two key figures are Ralph Stacey and Dave Snowden.
Human systems go by different names. Stacey refers to them as complex responsive systems, while Dave Snowden refers to human complexity as anthro-complexity.
Stacey has developed the Complex Responsive Process (CRP) theory, specifically in relation to human thought and communication. In contrast, Snowden has developed Cynefin, a decision-making framework that helps make sense of complex systems.
Snowden also writes about anthro-complexity—the complexity of human systems.
The key point that both Stacey and Snowden make is that human complex systems fundamentally differ from natural, biological, or technical complex systems in that each interacting agent is a complex adaptive system itself—a human being.
Snowden makes three points about human agents and speculates about more.
- We don’t just respond to stimuli; we can make choices.
- We substantially alter the world around us to suit our purposes.
- We shift between roles depending on the context and have developed rituals that allow us to temporarily align our identity with a role for a collective purpose.
Understanding human complexity helps us navigate interactions, decisions, and organizations more effectively. Applying insights from Stacey and Snowden can enhance our approach to working with uncertainty and change. Recognizing that humans are adaptive and unpredictable, we can develop better ways to communicate, collaborate, and make decisions in complex environments.
Detailed Resources
- Article: Embodied Cognition by Stanford Encyclopedia of Philosophy (2021)
Posts that link to this post
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- The Four Levels of Knowledge Management The relation between Conversational Leadership and Knowledge Management
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I thought life is simple, we humans made it complicated! Thanks for your critical analyses, which really made it complex! Was it necessary? Do we need AI to understand mother’s love?
Thank for your comment Rezwan. As individuals, we do not need to understand AI. And maybe at one time life was simple but as we connect globally, life has become more and more complex and we need to understand that if we are not to tear each other apart or if we are to adequately address global issues like climate change.