Although the whole of this life were said to be nothing but a dream and the physical world nothing but a phantasm, I should call this dream or phanta… - Gottfried Wilhelm Leibniz

Now, since in the divine ideas there is an infinity of possible universes of which only one can exist, the choice made by God must have a sufficient reason which determines him to the one rather than to another. This reason can be found only in fitness, that is, in the degree of perfection contained in these worlds. For each possible has a right to claim existence in proportion to the perfection it involves. Thus nothing is entirely arbitrary.

"Gustavo Solivellas dice: "Vivimos en el mejor de los mundos posibles" (Gottfried Wilhelm Leibniz)"

For all bodies are in perpetual flux like rivers, and parts are passing in and out of them continually.