  The main purpose of this paper is to attract the attention of researchers
working in the field of physiological processes, towards crucial events.
Crucial events are often confused with extreme events thereby generating the
misleading impression that their treatment should be based on quantum
mechanical formalism. We show that crucial events are invisible and should not
be confused with catastrophes. Crucial events are generated by
self-organization processes yielding a form of swarm intelligence, and signal
their action with fluctuations characterized by anomalous scaling and 1/f
spectrum. The existence or the lack of crucial events can be revealed with an
entropic method of analysis called the Diffusion Entropy Analysis (DEA).
However, anomalous scaling and 1/f spectrum are not a compelling signature of
efficient self-organization, and physiological processes with anomalous scaling
and 1/f noise spectrum without crucial events are a signature of collapsing
physiological organizations. In the case of physiological processes like cancer
dynamics, the existence of crucial events is a signal of intelligence that must
be destroyed rather than reinforced.
