Then you're asking for the impossible. The way they implement currencies like USD and EUR won't work for Bitcoins.

"We receive a wholesale rate quote from our bank twice a day and add 2.5% to determine the retail foreign exchange rate to apply to transactions that involve a currency conversion." - https://www.paypal.com/us/webapps/helpcenter/article/?solutionId=12900&m=SRE

You know a bank that quotes a wholesale rate for Bitcoins?

I read the petition and I can't figure out what you're asking them to do. Are you asking them to allow people to buy and sell Bitcoins using PayPal for the payment side? Are you asking them to sell Bitcoins themselves? Are you asking them to buy Bitcoins themselves? Or what?

It really doesn't matter. So long as the inflation/deflation is predictable and the inflation isn't due to an increase in supply not associated with an increase in real value and the deflation isn't due to a destruction of value, it all cancels out. In fact, you can argue that deflation equal to the average rate of investment return is optimal, as that permits those who want to minimize their risk to just hold currency, minimizing the transaction costs associated with choosing investments.

Perhaps by "poor people" you mean people who are extremely poor. But there are plenty of poor people who save up to put a down payment on a car. There are plenty of poor people who save to put their kids through college.

If salaries stayed the same in real terms, employers would have to negotiate reductions in salary to reduce salaries in real terms and every time an employee got a raise, it would be a real increase in their salary. But inflation games the system such that employees have to get regular raises just to stay put. This gives a huge advantage to the employer because he wins if no deal is struck.

The more your job pays and the more educated you are, the more likely that you can negotiate regular increases in your salary to keep up with inflation and even outpace it. The less your job pays, the less educated you are, and the more you are replaceable by others who do the same job, the less likely you can get your salary to keep up with inflation. Lawyers, CEOs, and professional athletes don't have much trouble, but cashiers, fast food cooks, and farm workers find it a bit more difficult.

And, of course, if you're talking about a pension or social security, you cannot negotiate a raise.

No, they're called suckers. Rich people are smart enough not to hold money, which they know loses value. Instead they hold things they expect to gain value, such as real estate, stock, art, gold, and so on.

Dirt poor people don't receive a paycheck? They don't have bank accounts? Inflation doesn't tax the dirt poor because the dirt poor have no value to take. It hits people just above that level the hardest.

You have it completely backwards. Inflation disproportionately burdens the poor, particularly by eroding the real value of their paychecks and secondarily by eroding their savings.

It's an indirect tax only on people who hold money though. If you tax windows, people will want fewer windows. Taxes that burden people in some kind of a just way are one thing, but taxes on specific, avoidable things cause people to dislike those things. Hidden taxes are even worse because they undermine the Democratic process that's supposed to control taxation and spending. Inflation is the worst type of tax -- one that is hidden, burdens the poor more than the wealthy (because they need to get raises in their salary just to keep it the same), but is avoidable by those who understand it.

They're still making more than they cost to power, and will continue to do so for about another five months. (Longer for others, I pay a ridiculous amount for power.) But they'll never pay for themselves. The more logical question is why I bought them in the first place -- and I did that because I think they're cool.

It won't happen. Even if you shut down the miners at the perfectly optimal time (before the power they use costs more than the Bitcoins they mine), you still won't make as much as they cost. I love these things and have nine of them mining behind me. But they'll never pay for themselves.

GIGO. You put nonsense numbers into the calculator. With realistic numbers, I get $144 in 90 days. My numbers:

Hash rate: 3300 Mh/s
Watts used: 100
Cost per KWh: 0.12
Cost of hardware: $400
Time frame: 90 days
Value per BTC: 126.8
Bitcoin difficulty: 86933017
Difficulty change per month: 30%
BTC per block: 25

Then you're just not looking very hard.

Refunds would cause customers to experience exchange losses. Someone who paid 39 Bitcoins for a Saturn two months ago would at most get 32 Bitcoins back, a loss of over $800.

But more importantly, if something gains value and then loses that value, you cannot argue that nobody was harmed. There can be people who bought in the middle, at the inflated price, who now are stuck with much less than they paid. Pro-orders have gained value. Someone who bought the right to a Saturn ordered two months ago for 45 Bitcoins today (which is reasonable) would be out the value of the expected profits that he had paid for, getting 32 Bitcoins back for the 45 Bitcoins he spent.

Loss of future expected value *is* a real present loss because expected values can be sold, traded, borrowed against, and so on. Of course part of the nature of future expected values is that they're accompanied by risk -- lots of risk. Everyone who has a pre-order has future expected value at risk.

I think the core objection to fiat money is that the issuer can create an unlimited quantity of it, depriving other people of value and imposing a hidden tax.

Eventually, it will cost as much or more to keep the miner powered than the value of the Bitcoins the miner makes. At that point, you have to power the miner down or you lose money. When people say a miner will "never make ROI", what they mean is that even if you run the miner until the ROI is at its maximum value, it will still be negative.

Proof is not needed. You just need to convince the escrow agency that it is more likely that you are telling the truth.

Then the buyer complains that the computer was broken. The escrow company (or an arbiter or whatever) decides who is more credible.

Same thing. The escrow company weighs the evidence and makes a decision or they employ a private arbitrator or whatever. Is it perfect? No. Does it provide some protection to both parties? Yes.

Yep. The key unknown is future difficulty.

KNCminder's choice of pricing models doesn't dictate my ROI calculations. What dictates my ROI calculations is what else I could do with the money, which is buy Bitcoins. Any idiot can buy Bitcoins -- if buying a miner is worse than buying Bitcoins, then only an idiot would buy a miner. If it's better than buying Bitcoins, then people who would otherwise buy Bitcoins should consider buying miners. From a realistic standpoint, your choices are to buy a miner, buy Bitcoins, or do something else.

The BTC price doesn't matter very much. It only affects the price of electricity in Bitcoins. Otherwise, everything else stays the same. You do the ROI calculation in Bitcoins and you compare buying a miner to buying Bitcoins directly.

The difference is that XORing can produce an output weaker than either input, concatenation cannot. The point is to protect against very unexpected failures without having to make assumptions about how well the underlying code is working. For example, you might write your code to use two different sources of entropy but then someone realizes that one of your sources is weak and so changes it to use a better source and now you're not using different sources anymore. Concatenation is robust, XOR is not.

The idea is to tolerate the unexpected case where source 1 and source 2 are similar or the same. XOR doesn't. The best imaginable algorithm can't produce an output stronger than the sum of the strengths of all of its inputs.

If we didn't have to tolerate unexpected cases, we wouldn't need any of this. An algorithm that can make things worse in unexpected cases is a bad idea, especially when it's so easy to make algorithms that don't.

I don't think there's any defect in using the hash of the concatenated seeds. Of course you have to choose an appropriate hash function, but other than that you should be fine. The output should be at least as strong as the strongest of the seeds you concatenated, up to the strength of the hash function.

We are comparing XOR to concatenation. And XOR is much worse. If you XOR two values that have a lot of bits in common, even if each of them is secure individually, the result of the XOR may be predictable, even if you hash it afterwards. If you concatenate, the result is at least as strong as the weakest thing you concatenated, even if you hash it afterwards (up to the strength of the hash function).

Agreed, but it's still important to prefer an operator that won't make it worse over one that will.