Against the backdrop of the scientific and technological revolution of the 16th and 17th centuries, a scientific worldview grounded in human reason and experience replaced theology as the dominant paradigm for understanding nature and society. The core elements of this modern worldview are determinism, atomism, and linearity. Determinism holds that the world, including society, can be perfectly explained by specific causal principles. Atomism posits that the world is formed through the mechanical combination of isolated elements, much like atoms, and that any object — including living organisms — can be understood through the process of breaking it down into its components and reassembling them. Linearity holds that all phenomena have clearly distinguishable causes and effects, and that specific factors produce specific outcomes in a linear manner — in a consistent direction and proportion.
This modern philosophy of science has contributed to humanity's intuitive understanding of the world by enabling the existence and changes of specific phenomena to be expressed concisely and economically. At the same time, modern scientific philosophy has aided in understanding and transforming nature and society by developing modes of thought and methodology: "concepts" that enable communication among people through generalization of phenomena, "theories" about the ways phenomena exist and change, and "measurement" that verifies abstract concepts and theories through concrete attributes.
Nevertheless, as numerous anomalous phenomena and cases have been observed — where causes and effects are difficult to distinguish, where causes and effects are in nonlinear relationships, or where the same factors produce different outcomes — persistent questions have been raised about the predictive power and problem-solving capacity of modern scientific philosophy. As a result, a new worldview on nature and society known as "complex systems" has emerged. Complex systems theory, when emphasizing nonlinearity, encompasses "chaos," a dynamical phenomenon extremely sensitive to initial conditions; "fractals," geometric patterns of "self-similarity" where small parts endlessly repeat structures resembling the whole; "catastrophe theory," where massive phenomena suddenly occur from random small stimuli, like an avalanche; and nonlinear "system dynamics" formed through feedback processes created by the information of stocks, flows, and time delays.
However, when focusing on the maintenance and development of biological or social systems, the concepts of "giant complex systems" or "complex adaptive systems" warrant attention. Giant complex systems refer to systems in which countless heterogeneous agents (elements) form multilayered structures while establishing diverse linear and nonlinear relationships. Systems of this type include the human body, the brain, natural geography, society, military operations, and warfare systems. These systems are also open in character because they exchange energy, information, and matter with their surrounding environments.
Open giant complex systems exhibit the following characteristics: emergence, where new properties (functions) that cannot be reduced to individual components arise from interaction processes among components; holism, a systemic property that cannot be understood as a simple aggregation of components; indeterminacy, where future system states (properties) cannot be determined due to the diverse possibilities of interaction among components; adaptability, the tendency to survive and maintain the system in response to environmental changes; historicity (path dependence), the inability to be free from existing experience and circumstances; and coevolution, the characteristic of changing or evolving in tandem with changes in the environment or other components. Warfare or operational systems, in addition to these characteristics, feature strong antagonism — where collision with other systems is a fundamental attribute — as well as jointness, where close interaction among components is critical for generating combat capability (operational power); real-time responsiveness, which demands immediate reaction (adaptation); and incompleteness in information and battlefield situation awareness.
In the age of new intelligence, ushered in by advances in Fourth Industrial Revolution technologies such as artificial intelligence (AI), networks, big data, virtual technology, biotechnology, and brain engineering, the characteristics of complex systems are evolving anew. With the formation and development of the Cyber-Physical-Social System (CPSS) through network and AI technologies, various problems are emerging as new types of giant complex systems appear — driven by the fusion of humans and machines, the merging of humans with virtual spaces, and the mass emergence of software-based or hybrid intelligent entities. For example, specific individuals or groups are using AI-based "network dynamics" technology to indiscriminately spread their claims or ideologies through social media platforms such as Instagram and TikTok, while the phenomenon of "information cocoons" is emerging, where people become captive to recommendation algorithms and their thinking hardens in extreme directions.
These problems are sending shockwaves through existing civil society and democratic systems, which are premised on critical reflection and rational participation by sound-minded citizens. Warfare and operational systems have also come to face diverse challenges with the advent of the age of new intelligence. In operational systems in particular, the issue of resilience is gaining prominence — where entire operational systems composed of various autonomous unmanned systems across land, air, and sea must recover combat power under indeterminate conditions caused by unexpected internal bugs or external interference such as electromagnetic spectrum attacks. Furthermore, operational systems in the age of new intelligence face the problem of adaptability — maintaining stable combat power through machine learning and evolutionary processes in response to rapidly changing battlefield environments. Alongside this, the issue of emergence is also newly arising, where diverse autonomous unmanned systems at both micro and macro levels must form operational capabilities through processes of "self-organization," "self-coordination," and "self-adaptation."
As Fourth Industrial Revolution technologies reach advanced stages and diverse intelligent entities proliferate in the age of new intelligence, the increasingly pronounced characteristics of complex systems — particularly around social issues — make it ever clearer that traditional scientific philosophy alone has limitations in achieving the healthy development of civil society or realizing national security.
Ultimately, the diverse complexities of the age of new intelligence can only be resolved through a complex systems perspective. From a coevolutionary standpoint, the concrete solution lies in the appropriate utilization of Fourth Industrial Revolution technologies.
