> What do you mean by "input prices" and "output prices"? What is
> price?
In the context that I was referring to, I intended "input prices" and
"output prices" to mean *market prices* for inputs (c & v) and outputs
(the commodity output).
> How can price be defined for "within a period"?
I'm not sure what you are asking. It seems to me that a "period" is an
abstract, logical unit of time. As we move to a lower level of
abstraction, we have to convert this concept into a unit of *real* time,
e.g. a year.
For the sake of discussion, I'll refer to a "period" as corresponding to
a 1 year period (I think this makes sense given Marx's previous way of
defining constant circulating capital).
> If one is
> talking about changes in prices over a period of time, then what
> does this changes in prices mean? If all 'prices' have doubled due
> to doubling of paper money supply, does this mean changes in
> prices?
If you are asking whether inflation will occur under these circumstances,
then the answer is yes.
I think, though, that the subject of inflation also has to be explained at
a more concrete level of abstraction. E.g. we need to explain how the
dynamics of (the changing form of) competition can lead to changes in
average prices.
Once one is talking about paper currency, one has already assumed the
state-form. The relationship, then, between state monetary policy and
price (in)stability needs to be explained.
In solidarity, Jerry