This page introduces the system theory with its feedback cycles used by this website in discussing two issues: (1) the development of human problems, and (2) escalating climate change. It looks at:

• Amplifying feedback in a sound system
• The cycles that organise predator and prey populations
• The amplifying feedback cycles of physical fitness and decline.
• The damping feedback cycle that controls a sailing boat’s direction.

The Audio Feedback Cycle

You’ve probably experienced audio feedback, that sudden, piercing screech from a sound system. Here is an amplifying feedback cycle that drives this audio feedback.

Diagram: The feedback cycle amplifying the screech of audio feedback.

In this audio feedback cycle:

• An increase in the microphone input volume tends to
• Increase the amplifier output of the sound, which tends to
• Increase the loudspeaker volume, which tends to
• Increase the microphone input volume, and then the cycle repeats.

The louder the screech gets, the louder it gets.

The Causal Links are Tendencies.

The causal links in feedback cycles are “tendencies” because other influences can override these links. For example, in a sound system, an increase in the microphone input volume tends to increase the amplifier output, but this does not have to happen. Normally, as the audio feedback gains volume, the sound operator can override this tendency by adjusting the amplifier settings to stop the feedback screech.

Amplifying Feedback Cycles in General

Any amplifying feedback cycle has a circular sequence of causal links between system attributes, in which an increase or decrease in one attribute tends to influence the next, which then tends to influence the next, creating a ripple effect around the cycle that then amplifies the initial change, enabling the cycle to repeat (Capra, 1996, p. 56).

Alternative Names for Feedback Cycles

You can call an amplifying feedback cycle:

• Positive feedback,
• Deviation amplifying mutual causal process (Maruyama, 1968)
• Self-amplifying feedback loop,
• Self-reinforcing cycle,
• Vicious cycle, and
• Virtuous cycle

You can call a damping feedback cycle:

• Negative feedback,
• Balancing feedback,
• Stabilising feedback, and
• Deviation counteracting mutual causal process (Maruyama, 1968)

Unrestrained Amplifying Cycles Limit Themselves.

Any unrestrained amplifying cycle will eventually exhaust some necessary resource and then pause its amplification, having significantly changed the system.

For example, the audio feedback could become so loud that:

• The amplifier reaches its maximum power and cannot send a stronger signal to the loudspeaker. On reaching maximum power, the amplifying cycle would pause after having completed its transformation of the system, leaving a high, constant-volume screech, or
• The loudspeaker blows a fuse. The vicious cycle would pause, having completed its transformation of the system, leaving silence.

Feedback Cycles Reveal Organisation.

A feedback cycle displays the organisation of the system, as distinct from its physical structure (Capra, 1997, p. 63).

Time Taken by the Audio Cycle

In this audio feedback cycle, each physical change takes time:

• The link between the loudspeaker and the microphone is via sound, which travels at 343 metres per second, so there is a small delay. Say the loudspeaker is 10 metres from the microphone, the sound travels that distance in 3 hundredths of a second.
• The link between the microphone and the amplifier is a rapid electrical connection, like when you flick a light switch, and the globe lights up; it seems instantaneous, but there is a small delay.
• The link between the amplifier and the speaker is another rapid electrical connection with a small delay.

Each causal link takes time as change ripples around the cycle. The rapid speed of the causal links in an audio system means that in small performance spaces, there is negligible delay between what you see and the amplified sound that you hear. The downside of the rapid links is that the feedback screech can rapidly escalate to an unbearable level – and the delays in the cycle are easy to overlook

Amplifying Feedback can be Intermittent.

In audio feedback, when it occurs, all causal links are active simultaneously. However, this is not a typical amplifying feedback cycle. I discuss several intermittent cycles on other pages:

• The cycle of natural variation and selection depends on intermittent events such as beneficial mutations, so the cycle has irregular bursts of activity.
• The warming Arctic ice albedo cycle does not reduce ice cover when it’s dark or freezing; it becomes active when it’s light and temperatures are above freezing.
• The amplifying cycle linking dread, gambling and gambling damage is also intermittent, as gambling and the gambling damage are both sporadic.

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Dominant, Active, & Reversed Cycles

An amplifying feedback cycle is:

• Dominant over a period in which, comparing the start and the finish of the period, each of the changes encouraged by the cycle occurred.
• Active, when one of the causal links is active.
• Inactive or dormant when none of the causal links is active. Intermittent: some causal links move between being dormant and active, for example, in the natural variation and selection amplifying feedback cycle, the cycle must wait for the intermittent occurrence of a favourable natural variation, e.g., a mutation. See the evolution cycles page. See the evolution cycles page.  
• Reversed: Some cycles can run in reverse. (see below)

I discuss dominance and reversal on the Arctic ice-albedo feedback cycle page.

Maruyama & his Second Cybernetics

Maruyama (1968) revolutionised systems theory by focusing on amplifying feedback cycles and their creative nature. He called his theory “the second cybernetics”, in contrast with earlier cybernetics, which focused on the control functions of damping feedback cycles and the destructive nature of amplifying feedback. According to Maruyama:

• Amplifying feedback cycles are widespread (p. 304).
• Amplifying feedback cycles can disrupt the existing order and create a new order. For example, rock weathering is an amplifying feedback process that is (1) a vicious cycle in that it destroys rock, but also (2) a creative, virtuous cycle in that it creates fertile soil and forests (p. 305).
• These feedback cycles interact and can support or counterbalance one another, producing stability, oscillation, or transformation. (p. 312).
• Amplifying feedback cycles between people can cause problems; for example, two aggressive individuals can easily escalate a misunderstanding into a physical fight.
• These cycles can also occur within a person, causing problems. For example, reduced self-confidence can lead to poor performance, which in turn can further reduce self-confidence (p. 312).
• In psychotherapy, the goal should be to break vicious, damaging feedback cycles underlying the presenting problem and to initiate virtuous feedback cycles that alleviate the problem (p. 312).

Damping Feedback Cycles.

Damping Feedback in the Audio System

When the sound operator hears the audio feedback building, they adjust the amplifier to eliminate the shriek. This control is called damping feedback or negative feedback. Here is a diagram of the damping feedback cycle.

More Deviation: Excessive Loudspeaker volume Less		More Control: The operator reduces the amplifier’s power. More

Diagram: The feedback cycle, which damps the screech of audio feedback.

In this damping cycle:

• More excessive volume tends to cause
• More control, which tends to cause
• Less excessive volume.

Damping Feedback in a Sailing Boat

The steering of a sailing boat is another example of a damping feedback cycle. I include this example of damping feedback because it has a clearer target than the audio example, i.e., the boat’s desired direction. Here is this damping cycle.

More Deviation: The sailing boat heads to the right of the target direction. Less		More Control: The sailor pushes the tiller further to the right. More

Diagram: The feedback cycle that damps the sailing boat’s deviation from course.

In this damping cycle:

• More deviation to the right of the target tends to cause
• More control: the sailor pushes the tiller more to the right, which tends to
• Reduce the boat’s deviation to the right.

Damping Feedback Cycles in General

In general, a damping feedback cycle is a circular sequence of causal links that triggers corrective action when a system attribute deviates from its target value, as in the sailing boat example mentioned above.

By contrast, the opposite occurs in amplifying feedback, where an increase in one system attribute causes a further increase in that attribute.

Reversible Amplifying Feedback Cycles

Some amplifying feedback cycles can operate in reverse. Here are several examples.

The Physical Fitness Cycle

You can become physically fit through training, but the reverse is also true: physical decline sets in when you do not exercise. Here is a feedback cycle amplifying physical fitness.

Do more of one physical activity until fatigued, and then allow recovery.		Increases your capacity to do the activity.

Diagram: The feedback cycle amplifying fitness.

In this cycle:

• Doing more of a physical activity, exercising until fatigued and then allowing time for the body to repair and strengthen the stressed tissues tends to
• Increase your capacity to do it, which tends to lead to
• Doing more of the activity, and the cycle repeats.

The causal links in this cycle are not certainties; they are tendencies, as other factors can intervene. For example, when the activity brings injury, doing more does not tend to increase your capacity to do it.

The Physical Decline Cycle

The training amplifying cycle also works in reverse: “If you don’t use it, you lose it”. In this amplifying feedback cycle:

Avoiding a physical activity.		Decreases your capacity to do the activity.

Diagram: The feedback cycle amplifying loss of ability.

The Audio Feedback Cycle is not Reversible.

The amplifying feedback cycle driving the audio feedback screech is irreversible. If a person put their hand over the microphone, reducing the microphone’s input volume, the cycle would not produce further decreases in volume. It would continue to increase the volume.

Arctic Ice-Albedo Heating Cycle is Reversible.

The Arctic ice-albedo heating cycle is currently amplifying global heating, but if cooling were to occur, it could also amplify global cooling. See my page on the Arctic Ice Cycle.

Predator-Prey Populations Cycles

I propose that it is clinically useful for a counsellor to apply some of the feedback cycles that organise human behaviour.

To demonstrate that this sort of modelling can be realistic, consider the interaction of three feedback cycles that can adequately model the populations of a predator and their chief prey: foxes and rabbits. In this model, there are three cycles:

• The breeding of foxes
• The breeding of rabbits, and
• The interaction between foxes and rabbits.

Here is the rabbit breeding cycle.

More Rabbits More		More Rabbit Breeding More

Diagram: The breeding feedback cycle amplifying rabbit numbers.

In this breeding cycle: (1) more rabbits tend to produce (2) more breeding, which tends to produce (3) more rabbits, and then (4) the cycle repeats.

The fox-breeding cycle has precisely the same form as the rabbit-breeding cycle:

More Foxes More		More Fox Breeding More

Diagram: The breeding feedback cycle amplifying fox numbers.

Now, foxes prey on rabbits, as shown in the following cycle.

More Foxes Fewer		Fewer Rabbits Fewer

Diagram: The feedback cycle organising the interaction between foxes and rabbits.

In this cycle: (1) more foxes preying on rabbits tends to produce (2) fewer rabbits, which tends to produce (3) fewer foxes, and then, extending this logic, this tends to produce (4) more rabbits, which tends to produce (5) more foxes, and then (6) the cycle repeats.

Mathematical models of predator-prey populations predict that these populations tend to oscillate, and investigation of natural populations supports this. See the Wikipedia entry on the Lotka-Volterra equations.

This example shows that amplifying feedback cycles can interact in complex ways.

Amplifying Feedback: Reinforcing & Inhibiting Influences

Here is an examination of the reinforcing and inhibiting influences on an amplifying feedback cycle. The following table provides an overview.

Inhibiting amplifying feedback

First, consider the things that can inhibit an amplifying feedback cycle.

Inhibitor: Exhausting a Resource.

The amplifying feedback cycle, when unimpeded, eventually exhausts a resource it needs to continue and pauses, having transformed its system. All unconstrained amplifying cycles eventually hit a limit.

Inhibitor: A Damping Feedback Cycle.

A damping feedback cycle can regulate and stabilise an amplifying feedback cycle. You can see this in the sound system example discussed above. As the audio amplifying feedback cycle escalates, the sound operator acts as the damping feedback cycle: adjusting levels, repositioning equipment, or applying filters to counter the runaway feedback.

Inhibitor: Other Feedback Cycles

Some amplifying feedback cycles can counter others. For example:

• The fox breeding cycle opposes the rabbit breeding cycle (See above).
• The vicious cycle escalating client Zed’s problem gambling could have opposed virtuous recovery cycles around his attending Gamblers’ Anonymous.

Inhibitor: External Events

External events can disrupt an amplifying feedback cycle. In a sound system, an electrical power failure would disrupt the audio feedback, although, because episodes of audio feedback are so brief, this would be an unlikely occurrence.

Reinforcement of amplifying feedback cycles

Reinforcement: An Amplifying Feedback Reinforces Itself

An amplifying feedback is self-reinforcing. Unimpeded, it transforms its system, destroying the old system and creating a new one. For example, the unimpeded audio feedback could blow a fuse in the sound system, leaving the event without sound.

Reinforcement: A Group of Amplifying Feedback Cycles

A group of mutually reinforcing amplifying feedback cycles can support one another. For example:

• Several types of amplifying feedback cycles work together to drive problem gambling, see human behaviour and feedback.
• Nine amplifying feedback cycles that drive global warming are identified on the linked page.

Reinforcement: External Events

External events can reinforce an amplifying feedback cycle. Global warming provides an example in which burning fossil fuels is the external influence that is reinforcing the amplifying feedbacks driving the warming.

Amplifying Feedback & Rapid Change

Once an amplifying feedback cycle becomes and remains dominant, it brings escalating change, initially slow and then explosive, until the transformation it initiates reaches a limit and the amplifying cycle stops.

For example, when a person in a chair leans back past the tipping point, a vicious cycle takes hold. The rotational energy increases as the chair tips. The only way to stop the vicious cycle is (1) an external intervention, e.g., someone catching the chair, or (2) the cycle running its course and hitting a limit when the chair hits the floor. See the tipping point of a brick & amplifying feedback page on this website.

Self-organisation and Chaos Theory

I briefly touch on complementary branches of systems theory: Chaos theory, which shows how feedback can produce complexity, unpredictability, and instability, and self-organisation, which shows how feedback can produce order.

• Self-organisation of human behaviour
• Chaos Theory (a work in progress)

Conclusion

When I worked as a problem gambling counsellor, I found amplifying feedback cycles useful for understanding and assisting my clients. The cycles help understand what drives and resolves problems. Then I realised that other amplifying cycles were driving global heating, and that systems theory provides insight into how any system works.

“Structures [feedback cycles] of which we are unaware hold us prisoner. Conversely, learning to see the structures within which we operate begins a process of freeing ourselves from previously unseen forces and ultimately mastering the ability to work with and change them.” (Senge, 1992, p 94)

Amplifying feedback cycles do not exist in isolation. Recognising how the influences discussed above can increase or decrease the impact of these cycles enhances the credibility of systems theory and our understanding of how amplifying feedback affects our lives and our planet.

My Systems Theory Pages

The feedback cycles organising human functioning:

• Human behaviour and feedback
• …
• Amplifying feedback organising habits (Weinberg)
• Amplifying feedback & psychodynamics (Malan)
• Amplifying feedback & cognitive interventions
• Symmetrical & complementary relationships
• …
• Self-organising human functioning
• Chaos Theory & Amplifying Feedback

Vicious cycles amplifying global warming

• Nine vicious cycles driving climate change
• The vicious cycle of migration, right-wing populism and climate inaction

Feedback cycles organising evolution

• Evolution of life on Earth: Virtuous cycles

The feedback cycles that emerge at a tipping point

• The tipping point of a brick & amplifying feedback

A feedback cycle supporting change

• A virtuous change cycle: Vision, Progress, & Benefits

Systems theory is critical to the two other topics covered by this website, and each has an overview page:

• Overview: Climate action pages
• Overview: Counselling pages

First loaded Nov 2025. Updated: 17 July 2026