Your definition of a living system would include a lot of mechanical and electronic devices. Certainly it would include the internet. In an attempt to be both abstract and bulletproof, something has been overlooked.
I have not tried to assert that matter is alive in any biological sense. I simply assert that there is no difference between living an non-living matter. Obviously the structure and behavior of biological systems will differ from non-biological things.
It seems to me it would be more fruitful to identify the specific processes associated with life and the required structures for engaging in those processes. The less abstract your list, the more useful for suggesting research.
I wish that you would do more than simply assert. The assertion has its logical consequences, the most problematic is that it renders naive experience illusory. Another problem is that it devolves into epistemological skepticism. Another problem is the loss of clarity as to a difference between life and non-life vs. living and non-living matter: is the organism derivative or additive attribute of matter? But perhaps I presume to much and now consider whether your assertion also implies that an organism is also non-existent.
Obviously, js1138. I agree with you: There is no difference between living and non-living matter qua matter. The point is everything that exists is made out of just one thing, matter -- which is uniform, ubiquitous, and (I would argue) drastically limited in its ability to articulate form -- either living or non-living -- from its own "internal resources." Plato inferred that matter -- chora -- was inherently "lazy." For it to do anything at all, it must be "told what to do," so to speak. That being the case, it seems to me that one must look further than matter per se in order to account for and qualify the astonishing variety of forms living and non-living that we see all around us.
I'm sorry you found my "list" abstract. But definitions that seek to qualify universal conditions are always abstractions. And unavoidably so, it seems.