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In response to Why bitcoin?
Comment author: trifith 02 April 2015 01:59:28AM *  4 points [-]

Bitcoiner here, so bear that in mind

A 51% attack is hard. It's come close to happening once with a mining pool called GHash.io. The community quickly responded, and as of right now, the largest pool has about 17% of the network hashing power, and GHash.io has about 4%. The current state of network power distribution can be viewed at https://blockchain.info/pools , as well as other blockchain watching services. It is in any particular miners interest to be in the largest pool possible, but counter to any miners purpose to be in any pool with the possibility of making a 51% attack, since a successful 51% attack would be the end of bitcoin's market value, which makes their investment in mining equipment worthless. This has, so far, been successful.

Each wallet does not need to contain the entire blockchain. It is generally recommended that, if you are not running a full node contributing to the network, you use a thin wallet that queries the blockchain, or a trusted blockchain monitoring service, in order to asses balances and get data needed to make new transactions in a much less data-intesive manner.

Governments are not keen to give up their monopoly on the money supply, but there are limits to how much they can do to maintain it. There have been several instances historically where government control of the money supply is undermined by the economic reality of people just using other things to conduct business, regardless of the legal status of such business.

Mining is not "wasted" computing power, but rather power being put to the specific purpose of verifying and securing the integrity of the bitcoin blockchain database. It is no more a waste of resources, than the concrete, steel, and construction time of a bank vault. It's just not doing anything else, like creating an emergency shelter, or storing non-bitcoin valuables.

If you have a non-currency based idea to get people to properly secure a publicly editable, decentralized, ledger such that malicious actors cannot alter it to suit their needs, I'm more than willing to hear it. Until I see such a proposal, I don't see the addition of currency to a blockchain as a complication, but rather as a necessary function. There has to be something which incentivises people to engage in the process of securing the ledger, and that is the receipt of valuable entries on the ledger, those entries being useable as currency.

In response to comment by trifith on Why bitcoin?
Comment author: Grant 02 April 2015 04:50:58PM *  2 points [-]

It looks like other blockchain technologies (altcoins) have been the victim of 51% attacks, so I'm going to read up on their repercussions. I wonder if they were carried out by bitcoiners who don't like competition?

It occurs to me that little can probably be done to stop attacks on distributed systems by large actors with non-monetary goals. If people are willing to throw a lot of resources into destroying a fledgling technology, they will probably succeed.

I do have an idea for a distributed public ledger in which attacks are possible but always negative-sum. I have little experience with cryptography so its probably rubbish. If it looks to not be terrible I will probably post it here for comment.

In response to Why bitcoin?
Comment author: trifith 02 April 2015 01:59:28AM *  4 points [-]

Bitcoiner here, so bear that in mind

A 51% attack is hard. It's come close to happening once with a mining pool called GHash.io. The community quickly responded, and as of right now, the largest pool has about 17% of the network hashing power, and GHash.io has about 4%. The current state of network power distribution can be viewed at https://blockchain.info/pools , as well as other blockchain watching services. It is in any particular miners interest to be in the largest pool possible, but counter to any miners purpose to be in any pool with the possibility of making a 51% attack, since a successful 51% attack would be the end of bitcoin's market value, which makes their investment in mining equipment worthless. This has, so far, been successful.

Each wallet does not need to contain the entire blockchain. It is generally recommended that, if you are not running a full node contributing to the network, you use a thin wallet that queries the blockchain, or a trusted blockchain monitoring service, in order to asses balances and get data needed to make new transactions in a much less data-intesive manner.

Governments are not keen to give up their monopoly on the money supply, but there are limits to how much they can do to maintain it. There have been several instances historically where government control of the money supply is undermined by the economic reality of people just using other things to conduct business, regardless of the legal status of such business.

Mining is not "wasted" computing power, but rather power being put to the specific purpose of verifying and securing the integrity of the bitcoin blockchain database. It is no more a waste of resources, than the concrete, steel, and construction time of a bank vault. It's just not doing anything else, like creating an emergency shelter, or storing non-bitcoin valuables.

If you have a non-currency based idea to get people to properly secure a publicly editable, decentralized, ledger such that malicious actors cannot alter it to suit their needs, I'm more than willing to hear it. Until I see such a proposal, I don't see the addition of currency to a blockchain as a complication, but rather as a necessary function. There has to be something which incentivises people to engage in the process of securing the ledger, and that is the receipt of valuable entries on the ledger, those entries being useable as currency.

In response to comment by trifith on Why bitcoin?
Comment author: Grant 02 April 2015 02:13:22AM 0 points [-]

Thanks, I did not know about https://blockchain.info/pools.

On the 51% attacks, I was specifically thinking of state actors. However, mightn't any eventuality which leads to a lot of Bitcoiners who aren't enthusiasts or have ulterior motives (Bond villains?) be an issue? The current state of the BC community is probably mostly BC enthusiasts, i.e. people who aren't just in it for the money.

You're right that "wasted" was a poor term; "inefficient" would be better.

Why bitcoin?

3 Grant 02 April 2015 01:24AM

I'm a software dev who is considering becoming a bitcoiner, mostly to explore its possibilities. I think a currency free from the baggage of the modern financial systems will allow great things to be done. I see lots of other people are thinking the same way (there are numerous BC prediction markets, for example).

However, I don't want to invest time and money in a seriously flawed or doomed system.

BC appears to have at least one potentially-fatal flaw: the 51% attack. I'm unsure why it was assumed this would not be a problem? Profits from mining would seem to increase when on reaches over 50% of the world's mining power. This would seem to encourage powerful mining pools. While current norms and other incentives may discourage black-hat miners, I don't think it is reasonable to rely on these incentives.

Edit: In other words, is there an economy of scale in being the dominate miner?

Edit 2: While it looks like there was a successful BC double-spend, it was the result of a white-hat exploiting a bug, not a 51% attack. However, a few altcoins (e.g. reddcoin) have been the target of 51% attacks, so my research on their repercussions will start there.

In addition, BC would appear to have a number of other flaws:

  • The necessity for each wallet to contain the entire block chain. Edit: Apparently I was reading some dated information. This is wrong.
  • Governments have never seemed keen to give up their monopoly on the money supply.
  • The computing power wasted by mining.
  • It complects the generation of a public ledger with a specific currency.

Side note: After reading about BC and 51% attacks, I am beginning to think "the network effect is the mind killer" might be a more general expression of "politics is the mind killer". There is a lot of noise out there.

Help and insight is appreciated.

Comment author: Grant 27 March 2015 05:55:53PM 0 points [-]

Why does anyone think BitCoin is going to work when its users aren't mostly BitCoin enthusiasts?

I'm specifically referring to incentives of 51% attacks. The returns on mining seem to increase as computing power eclipses 50%, creating an economy of scale in mining and incentivicing attacks.

Comment author: satt 07 March 2015 10:03:57PM 7 points [-]

I am a scientist, albeit the most junior kind of scientist, and I reckon "science" can legitimately refer to a set of answers or a methodology or an institution.

I doubt anyone in this thread would object if I called a textbook compiling scientific discoveries a "science textbook". I'm not sure even Taleb would blink at that (if it were in a low-stakes context, not in the midst of a heated argument).

Comment author: Grant 26 March 2015 06:57:22AM 0 points [-]

The information in a science textbook is (or should be) considered scientific because of the processes used to vet it. Absent of this process its just conjecture.

I often wonder if this position is unpopular because of its implications for economics and climatology.

Comment author: D_Alex 23 March 2015 06:33:40AM 0 points [-]

If we need to look to economics for rationality quotes, we are getting towards the bottom of the barrel, Robin Hanson notwithstanding.

Comment author: Grant 26 March 2015 06:36:51AM *  2 points [-]

Macroeconomics? Sure, its highly politicized so in many cases I'll agree with that. But microeconomics is in many ways the study of how to rationally deal with scarcity. IMO, traditional micro assuming homo-economicus is actually more interesting (and useful, outside of politics) than the behavioral stuff for this reason.

Comment author: Grant 04 March 2015 07:42:31AM 2 points [-]

Is there overwhelming evidence on the safety (not efficacy) of vaccines somewhere, and I've just missed it?

Comment author: Grant 06 December 2014 06:50:04PM 0 points [-]

I used to just trust the word of the experts, because I am not an expert and had no incentive to become one. I didn't have a lot of faith in such a politicized science, but reasoned it was probably better than anything I could come up with. I trusted the IPCC reports, but after reading about Climategate thought they were exaggerated a bit as a means to gain political power.

Recently I've started to consider investing in alternative energy. Given that most alternative energy (especially with the fracking and shale oil revolutions) is based on AGW being a serious problem, I thought it deserved a real look.

I was appalled to see a non-experimental science call something as complex as the Earth's climate to be "settled", and how even the scientists seemed to degenerate into name-calling ("deniers" and "alarmists"). The issue was even more politicized than I first thought. I was unable to find real public debate between skeptics and supporters, but did come to understand that the disagreement is over feedbacks, specifically the change in water vapor, which respond to an increase in temperature from CO2 emissions.

I was most appalled at the lack of reporting of the global warming pause. I did not find a single supporting scientist seriously reconsider his views in light of the pause. One would think admissions such as "our models were clearly wrong, but AGW may still be a problem because the heat is probably going into the oceans/arctic/whatever" would be commonplace.

To me the "science" of climatology seems very similar to economics: experiments are impossible and it is very politicized. I enjoy and respect economics greatly, but recognized that progress in it has been very slow relative to the harder, experimental sciences.

As a result my faith in climatologists is at an all-time low. If I had to guess, I'd take a shot in the dark and say the feedbacks are being exaggerated by the IPCC, and warming will continue at about 0.10 degrees C per decade. Actually I'd say this whole experience has lowered my faith in politics and made me more libertarian as a result. I am used to people doing and believing disgusting things for power, but something about perverting science especially offends.

So I came here to read some (hopefully) more rational reports on AGW.

I would really like to see a study of the Earth's energy budget - can't we measure radiation lost to space with satellites? Everything else seems rather immaterial (unless the nuclear energy output of the Earth's core varies significantly).

I just read the OP's articles. There is a supporting argument in them which makes me think my sensitivity estimates are too low: the idea that sensitivity can be estimated from any source of forcing (of which there are many), and not just CO2. This would seem to suggest that we have more evidence on climate sensitivity (even if its all proxy records) than I'd of first guessed. However, unless proxy records can cover all significant forcings, I would doubt their usefulness. Do we have a proxy record of cloud cover, for example?

Comment author: brazil84 26 March 2014 07:44:09AM 3 points [-]

Since holding irrational beliefs tends to result in eventually loosing one's wealth and power,

I'm not sure this is true because of standby-rationality mode. Also known as hypocrisy.

Comment author: Grant 26 March 2014 08:21:58AM 3 points [-]

Agreed. Powerful people (especially politicians) seem to hold plenty of irrational beliefs. Of course we can't really tell the difference between lying about irrational beliefs and hypocrisy, if there's a meaningful difference for the outside observer at all.

Comment author: hankx7787 27 October 2013 02:28:27PM 4 points [-]

Completely wrong.

As a software engineer at a company with way too much work to go around, I can tell you that making a "good effort" goes a long way. 90% of the time you don't have to "make it work or get a zero". As long as you are showing progress you can generally keep the client happy (or at least not firing you) as you get things done, even if you are missing deadlines. And this seems very much normal to me. I'm not sure where in the market you have to "make it work or get a zero". I'm not even convinced that exists.

Comment author: Grant 29 November 2013 02:53:28AM 0 points [-]

The quote refers to the (end) market and users, not the internal workings of a software development firm.

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