Resistance is opposition, or slowing down, of one force by another.
The chemist Le Chatelier first used the term ‘path of least resistance’ when referring to a chemical reaction. When an object or event encounters a minimum of opposition, it follows the path of least resistance.
The more coherent a system, the more resistant it is to opposing forces. The less coherent a system, the less resistant it is to opposing forces.
Coherence is related to predictability. A random motion is unpredictable by definition. Branching patterns are more predictable than random motions. Circular and spiral patterns are more internally similar, therefore more predictable than either branching patterns or random motions.
Typically, a simple system behaves in a predictable manner, while a complex system displays unpredictable behavior. Fractals are simple. The weather or stock market is complex.
Simplicity and complexity are not necessarily related to size or scale. Stars are less complex than insects.
The simplest coherent pattern is a wave. A wave vibrates about a position of equilibrium, following, with great fidelity, the path of least resistance. Electrons and quarks are the simplest arrangements of matter. They follow a clear path of least resistance. They form a simple, repetitive pattern within a confined region. Molecules are more complex than atoms. They have more components, a greater variety of motion, with more opportunity for unpredictable behavior, and greater potential for friction.
A human brain is the most complex system in the known universe. Brain functions are involved in complicated, often messy, decision making.
The relationship of life-forms to the path of least resistance is itself complex. Equilibrium is a state of least resistance, where entropy is lowest. However, far from equilibrium, as in life-producing processes, the dissipation of energy may become a source of order. Biochemical order is maintained by energy exchange with the environment.
In its habitat, an organism may follow different paths of great and less resistance. For example, complex DNA molecules express unpredictable behavior, including mutations. Yet, DNA may be seen as a simple copying machine, replicating the same genes generation after generation. Life perpetuates life. In fact, I propose that DNA is the longest lasting perpetual motion machine on earth, continually rallying against the second law of thermodynamics.
Some organisms are more complex than others. Fungi, plant and animal cells, known as Eukaryotes, are unicellular organisms that contain a true nucleus, plus various organelles. They are more complex than primitive single-celled organisms, or bacteria, known as Prokaryotes. The potential for unpredictability is greater in plant and animal cells than in bacteria. Animal and some plant cells recombine genes through a complex process of sexual reproduction, with programmed cell death and other aging processes as a necessary byproduct. Plant and animal cells follow a path of greater resistance than bacteria. Bacteria reproduce through a simple bifurcation process, and are immortal. They follow a path of less resistance than plant and animal cells.
Ironically, for many creatures, including humans, behavior that is most adaptive does not always follow the path of least resistance. Evolutionary symbiosis, the long-term partnership between two or more species, is a clear example. Another is human behavior. An individual, for instance, may decide to sacrifice years of conflict enrolled in institutional education in order to secure a less stressful future. Humans routinely experience emotional stress or turmoil caused by complicated, unpredictable behavior between individuals or groups. Family, friend, and peer conflicts resulting in prolonged anger and distrust are commonplace. The amount of conflict and resistance between people is likely a result of our deeply evolved social organization. Thankfully, complex rules and mores of social order provide a significant level of bonding, love, and nobility, a clear survival advantage. A certain amount of emotional suffering and turmoil, a path of great resistance, is simply one of the costs of human evolutionary adaptation.