There are many physical systems that increase in complexity. How about growing crystals? Plants? The world?
The world? Okay, let's kick down that ol "subtle and deep thought" pedal right to the hard pavement on this virtual shovelhead.
So then here it is: The very physics of the universe being as intricately fine, beyond any rationally ability to so occur as happenstance. Can only mean intelligence of the unimaginably highest order.