Humanity

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In general, there are two types of change that take place in the Universe: catastrophic and evolutionary.

A catastrophic change is characterized by a large alteration of conditions in a short period of time. An evolutionary change is characterized by slow alterations of conditions over a long period of time.

Clearly, catastrophic change is more dramatic, but if we observe the Universe around us, it is equally clear that evolutionary change is the rule.

A star shines for anywhere from many millions to many billions of years, slowly evolving, until it reaches a point where (if it is large enough) there is an overbalancing, so to speak, and, in the space of a few minutes or a few hours, it explodes as a supernova and collapses. Catastrophe! But, thereafter, it exists as a white dwarf, neutron star, or black hole, and returns to prolonged evolutionary change.

Again, a huge cloud of dust and gas slowly circling and condensing undergoes evolutionary change, until its center reaches the level of temperature and pressure where nuclear fusion can begin. There is then ignition and a sun is born. Catastrophe! But, thereafter, a planetary system evolves over the space of a few million years, achieves equilibrium, and continues to evolve over the space of a few billion years.

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