SB 12.4.29

vikāraḥ khyāyamāno ’pi
 pratyag-ātmānam antarā
na nirūpyo ’sty aṇur api
 syāc cec cit-sama ātma-vat
Synonyms: 
vikāraḥ — the transformation of created existence; khyāyamānaḥ — appearing; api — although; pratyak-ātmānam — the Supreme Soul; antarā — without; na — not; nirūpyaḥ — conceivable; asti — is; aṇuḥ — a single atom; api — even; syāt — it is so; cet — if; cit-samaḥ — equally spirit; ātma-vat — remaining as it is, without change.
Translation: 
Although perceived, the transformation of even a single atom of material nature has no ultimate definition without reference to the Supreme Soul. To be accepted as factually existing, something must possess the same quality as pure spirit — eternal, unchanging existence.
Purport: 

A mirage of water appearing in the desert is actually a manifestation of light; the false appearance of water is a specific transformation of light. That which falsely appears as independent material nature is similarly a transformation of the Supreme Personality of Godhead. Material nature is the external potency of the Lord.