Defining Literature Part 2

What type of “definition” are we talking about here? Do we mean a semantic, or lexical definition, for example? Must this definition be completely “closed”, or can it remain somewhat “open”? When I think of  the term "definition", I imagine a closed lexical definition, something that is both universal and everlasting (that is, that it is true everywhere across time). However, I recognize that if we try to define the term "literature" with that kind of definition, we will inevitably fail. As with most of the arts, it appears that a more open definition is required. But then we fall into another problem, the problem of radical inclusivity. How open can we make the definition while still retaining some proper criteria? And there is another problem with defining literature; can literature be measured on a scale, or must it be binary? That is, must a work either be or not be literature? Although a binary definition does seem to be more closed, surely not every written work can be a work of literature. And if we were using a binary type definition, should we then only use a scale to measure how well a work succeeds at being literature? We need to first decide on how we are going to define "literature" before actually trying to decide upon the criteria it will need to satisfy.