@tee-rex #176:
TBH, I was hoping for a more mathematical argument than what you give in #176, I just find algebra easier to follow than words (maybe because it's less ambiguous).
Anyway, you seem to be making a point about profit. TBH, I hadn't analysed that, but having slept on it have now done so and am still of the opinion the two flations are mirror images (perhaps complements, or conjugates, is a better term. But, as I inclined above, I'm not that good with words).
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Here's how I see it.
First, if inflation is p (per week) then the corresponding deflation is q = -p/(1+p) [1].
Say a trader has production costs W and sells what is produced for R = 2W, each week (it's a little easier if we assume 100% mark up).
If now inflation kicks in at p, then on the first week W_1 = W(1+p) and R_1 = R(1+P), thus maintaining R/W = 2.
And on the kth week W_k = W(1+p)^k and R_k = R(1+p)^k, again maintaining R/W = 2.
The deflation case is trivially the same, with p replaced by q = -p/(1+p), and we find R/W = 2 as above.
That's it really.
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Also, others support my view[2]. Sorry, but I haven't had time to find a specific file, but you can scroll through some of the contents of the books in [2]. Ah, just managed to load this[3] (it was taking forever last night so I gave up), in which the 4th para starts, "Inflation's mirror image, deflation, has less of a dark historical legacy". I haven't read it all so don't know if it says much more about them being mirror images. It would be nice to find a pdf, or what ever, giving an argument for or against my assertion. If you manage to find such please let me know. Still, I do find it a useful guide, but maybe that's because symmetry has always been strong in my thinking, in fact even before I knew it was called symmetry.
[1] This is easily proved: If a period of inflation is followed/preceded by a complimentary period of deflation then the total inflation/deflation must be 0, thus we require (1+p)(1+q) = 1.
[2]
https://www.google.co.uk/?gws_rd=ssl#q=deflation+is+the+mirror+image+of+inflation[3]
http://www2.hmc.edu/~evans/inflation.pdf