Nonsense. You can't easily specify the difference between a dog and a wolf, but you can cite examples of each.
As we learn more about chemical evolution we come closer to understanding what conditions are necessary to produce replicators. And as we do it will become increasingly difficult to draw a line between life and mere chemistry. This does not mean we cannot understand the what is happening. It simply means that categories are constructs rather than things.
Poor analogy. A taxonomist can easily explain the differences between a dog and a wolf. A biologist can not easily define what is life. Even if you had a sea of RNA or DNA, what you would have is bunch of inert chemicals that replicate in the same manner as cyrstals. No one can call them living things.
BTW - dogs are a subspecies of wolf and while some dogs have most of the characteristics of wolves, most do not. The fur, jaws, and feet differ from wolf to domestic dog.