[glenstein]

The way I like to think of it is that life, most broadly and abstractly conceived, falls like water through the space of possibilities afforded by nature, and there is no limit to how complex that "shape" can be (where "shape" is something in a space of possible combinations of forms, mechanisms, tools that are simultaneously used by one organism, a search space of possible combinations rather than a literal shape).

And whatever "intelligence" it would take to consciously think from first principles to those kinds of shapes, well, there's no upper limit to the possible sophistication that might be required to manually get there. But nature gets there blindly, and uses every possible thing.