“People no longer try to decipher the mystery of life but choose instead to be a part of it.”

Source: Are We There Yet?

Variants:
Science cannot solve the ultimate mystery of nature. And that is because, in the last analysis, we ourselves are a part of the mystery that we are trying to solve.
Science cannot solve the ultimate mystery of nature, for in the final analysis we ourselves are part of the mystery we are trying to solve.
Source: Where is Science Going? (1932)

Parrots, the Universe and Everything (2001)
Context: For us, there is no longer a fundamental mystery about Life. It is all the process of extraordinary eruptions of information, and it is information which gives us this fantastically rich, complex world in which we live; but at the same time that we've discovered that we are destroying it at a rate that has no precedent in history, unless you go back to the point when we are hit by an asteroid!

Source: Path of Life (1909), p. 210

Source: Shadow Kiss

Fragment ix.
Golden Sayings of Epictetus, Fragments

As quoted in Introduction to Philosophy (1935) by George Thomas White Patrick and Frank Miller Chapman, p. 44
Variant translations:
I am satisfied with the mystery of life's eternity and with a knowledge, a sense, of the marvelous structure of existence — as well as the humble attempt to understand even a tiny portion of the Reason that manifests itself in nature.
Enough for me the mystery of the eternity of life, and the inkling of the marvellous structure of reality, together with the single-hearted endeavor to comprehend a portion, be it never so tiny, of the reason that manifests itself in nature.
1930s, Mein Weltbild (My World-view) (1931)

Historical essays (2001)