In a [lecture](http://audio.simpletoremember.com/gottlieb/Evolution_age-of-the-Universe.mp3) on science, Rabbi David Gotlieb states that the purpose of nature is to provide a misleading appearance that the world carries itself, and the purpose of that is to provide an arena for human free will.

Are there any sources which say this explicitly? (preferably from scripture if possible)

Best I can see, is Deuteronomy 30:19 (..choose life), but that just says regarding the blessings and curses. It does not say that the purpose of creation of this world is as an arena for man's free will.