  Danger requires a strong rapid response. Speedy triggers are prone to false
signals. False alarms can be costly, requiring strong negative regulators to
oppose the initial triggers. Strongly opposed forces can easily be perturbed,
leading to imbalance and disease. For example, immunity and fear response
balance strong rapid triggers against widespread slow negative regulators.
Diseases of immunity and behavior arise from imbalance. A different opposition
of forces occurs in mammalian growth, which balances strong paternally
expressed accelerators against maternally expressed suppressors. Diseases of
overgrowth or undergrowth arise from imbalance. Other examples of opposing
forces and disease include control of dopamine expression and male versus
female favored traits.
