Without God there is no justice. Since I have the impression of justice, then it must exist. Existence applies to concepts as well as matter. Since Justice is real and a pursuable concept, it must exist outside of man. If it cannot possibley be attained on earth, then it must be attain outside of our current reality, the meta-reality, the true reality.
Life is the same.
We are merely shadows of the glory that is to come. The real things we see, and believe, are real everywhere and outside of our perception. There is a subtle slight of hand here. What Bertrand uses for analogy is testable experience such as decaying fruit. But what I speak of is the concept of Justice is innate in mankind.