The equation 5.3.1
for "Earth 2" with an intelligent species can
be extended to:
Equation 6.3.1 shows the number of intelligent species that may have technology and have reached a development level greater than 2. Equation 6.3.1 can be simplified a little further. To do this, you have to look at the probability factors. The following are known:
If you only look at "Earth 2", you can still establish a probability for a civilization:
F_{z}
must be adapted to the quantities of civilization to be
considered, which will become apparent in the following
sections.

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