Hi Spook,
Fine, you have very small robots with no nano-techknowledgy. Cells are biological, so you're not talking about bots at all.
Why do cells have to be 'biological'? The arrangement works very well for organic life forms, why should it not also work for inorganic life forms?
You either have very small robots (synthetic non-life) or you have organisms.
'organism' would seem to be a combination of 'organic' and 'ismitsm' (old red-indian word for active), so no, I don't suppose you can have an inorganic organism. But my nanobots meet your original criteria for life, so why are you kvetching about it now?
The bottom line is that in your illustration ...
1. The fact is the presence of "nanobots."
Check!
2. Seeking to explain this, you form an hypothesis.
Check!
3. The factthat there are "nanobots" can not be evidence for this hypothesis used to explain the existence of nanobots. Because "nanobots" are the artifact in question.
What hypothesis? That an inorganic 'life' form can originate and evolve? Isn't that exactly what evolution hypothesises about organic life? On exactly the same premise but inversed? Or do you mean the hypothesis that someone designed them and put them there?
4. If you already knew aliens existed for sure as a fact, but were unsure if they had created nanobots, then and only could you use the traits of the "nanobots" by comparison to OTHER objects of known alien design and create an argument from comparison that aliens created the nanobots.
Eh? We can only create an-argument-from-comparison that aliens created the nanobots if we already knew aliens existed for sure as a fact and already have some artifacts that we know for a fact they designed? Well, we won't 'cos we don't and we don't. Now what?