It's not so much an inflation, but an expense as result of PoW mining, everyday $1.5M is transferred from the Bitcoin eco-system, into the pockets of ASIC hardware vendors and electricity companies.
I disagree: mining difficulty follows the price, not the other way around. If miners start to find it unprofitable, the hash-rate will drop. Less efficient miners drop first.
POW is important because it requires an attacker to expend scarce resources: something POS based currencies do not. The problem with POW is that we still do not know for certain it will work in the long-term. Bitcoin is still very much an experiment.
Wrong, it's extremely easy and cheap to attack PoW network, tons of PoW altcoin has been attacked to death.
Zero successful 51% attack on any PoS altcoin so far.
Because:
1. it's extremely expensive to acquire 51% stake
2. once you acquire 51% stake, why would you attack anymore? YOU are the majority stake holder, you want to attack yourself? and destroy the reputation and value of the coin you hold 51% stake in? why would you destroy your own wealth? it won't make any sense.
Quite a bit of twisting of facts.
It's as "easy and cheap" to attack a PoW network as the cost of specialized hardware and electricity that goes into securing it. For alts, that's a real problem, agreed. For Bitcoin, this risk is becoming more and more hypothetical.
There are numerous reasons to prefer PoW over PoS, but I'm going to guess it'll be pointless to have this argument now. Preferring one or the other is a major point of divergent opinions, as far as I can tell.
The cost to 51% attack Bitcoin is roughly 10% of Bitcoin marketcap, or around $500-$600 million, this is enough to buy more than enough hardware to vastly outnumber the current miners, agreed?
Now if Bitcoin is proof of stake, you need to buy 51% of all Bitcoin available. It's not going to cost you 10%, nor 100%, but more like 1000% or more of Bitcoin marketcap to purchase 51% of all Bitcoin available.
So how can you argue that compared to PoS, PoW is not cheap and easy to attack?
There's no real difference between Bitcoin and PoW altcoins, other than Bitcoin is far bigger. But still, if the attacker has large enough resources, he could attack Bitcoin. Just like current miners find it real cheap and easy to attack a smaller PoW altcoin. It's at least 100X more difficult to attack Bitcoin if Bitcoin was PoS, just like no one could attack even a tiny PoS altcoin, due to cost.
Alright, since you're not giving up, here's the rebuttal, in shorthand:
1) 51% attack against Bitcoin is infeasible, both by prohibitively high cost for any but the largest entities, lack of economic incentive (cost of attack > profit resulting from attack, because market value would drop as an effect of the attack), and the near-impossibility to secure and put online, in complete secrecy, the specialized hardware (regardless of the USD cost of the hardware). Don't care about PoW vs. PoS in alts.
2) PoS is inferior to PoW in three key regards: New coin distribution according to work is vastly preferred over distribution according to stake. Can't argue with human nature. Consensus forming in the case of competing chains is trivial for PoW, and bordering on impossible for PoS. The economic backing of PoW in the form of energy exerted provides a useful base valuation, because it provides the network with a well-grounded "bootstrap" value.
Questions?