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You should give it to everyone; because otherwise there is little incentive for people below the guaranteed income level to work.

Really? I live off of ~ $10,000 per year. I'm poor. Everyone. Even if they earn $100 trillion dollars. Using a threshold creates a severe disincentive to work for the people around the threshold, so doesn't maximize social welfare. People should earn what they produce. Maybe at the lower end. Is that an issue? You would get lower unemployment. And some people would work more, and some people would not be unemployed. Given that we aren't comparing a specific flat tax + guaranteed income with a specific 'progressive' tax system, I don't think one can determine a priori if more or less government revenue is coming in. Also, whether the size of government increases or decreases shouldn't trump whether a tax system increases the social welfare of society.

And why should there be this artificial expectation? I certainly don't have it. People should earn what they produce. If the economic value of someone's work isn't adequate to obtain a 'living wage' (maybe they are disabled for example) then they shouldn't obtain it. All you achieve with this expectation of yours is put people out of work and increase unemployment (as well as increase prices on goods and services). Since companies won't generally hire someone if they don't earn them at least as much money as they cost. If you want people to have enough money to live off of, give it to them via a guaranteed income. It would change the incentives to work; there are tradeoffs. For example, the extreme poor might have a lower incentive to work but the extreme rich might have a higher incentive to work. But given that richer people generally produce more goods and services than poorer people per unit time, this can result in more goods and services being produced. So by going to the flat tax + guaranteed income it might be possible to get a society that both produces more goods and services and has a more equitable distribution of those goods and services. Also, if the poor people aren't working, they might be doing something else productive with their time (such as acquiring skills). Having the extreme poor spend all their time working in low skill employment means that they can't spend time to improve their skills and thus you create a poverty trap where the extreme poor remain poor. If a person can only produce $2 per hour working, then that is what they should get paid. If their wage accurately reflects the value of their work then the individual will make decisions about how to spend their time that maximize the social welfare of society. If the individual finds that they'd rather spend an additional hour playing video games than earning $2 working and they only produce $2 when working, then the individual should play video games because that is what maximizes the social welfare of society.

I guess so. I should have specified the monetary incentive to work. Obviously there are other factors in determining if a person decides to work or not. People in general, yes. Teachers specifically? That's harder to say given that it has a government employer and is heavily unionized. Participation rate is not the same thing as how many hours per week people decide to work (or if they decide to work more stressful jobs). I'm not sure how you quantify 'burden', so I cannot verify your claim. I am not sure what your definition of social injustice is, but I do think it is unfair. People can plan 10+ years in advance. How else do you explain people retiring, people having children and saving money so they can go to university, people obtaining mortgages, etc.? Also, if people have an unstable income, they can always use a bank to save/borrow money so that their consumption is smooth over time.

You can design it such that it's revenue neutral. The larger the flat tax, the larger the guaranteed income.

Yes. You could set both the guaranteed income at 0 and the flat tax and 0 and you basically have extreme libertarianism. Or you could set the tax rate to 100% and redistribute all the income evenly to everyone and you basically have communism. Or you can do anything in between. It has the advantages of being simpler and of satisfying that fisherman fairness property. It reduces the problem of developing an optimal tax system to a single dimension (trying to find the optimal flat tax, because if you wish to satisfy revenue-neutrality, the guaranteed income is determined by the flat tax). As for the socially optimal flat tax, it might be possible to find it using empirical data.

I think we should. Guaranteed income + flat tax. Far more preferable and less distortionary than welfare + minimum wage + tiered tax system + employment insurance.

Yes, keepitsimple was advocating a type of progressive tax (exemption on first $x of income then flat tax after that). Provided that we use the definition that a progressive tax is a tax such that the proportion of income people pay as tax is a non-decreasing function of income (as opposed to increasing as I mentioned earlier). Edit: but if we use this definition, then a flat tax counts as progressive.

I don't get this implication. How does lack of perfect information about the universe by governments imply that flat taxes are dumb? You may not know exactly why an individual made more money compared to another individual, but you can use empirical data and statistical techniques to test hypothesis as to why statistically people achieve certain outcomes. From there, you try to maximize expected social welfare.

For the sake of clarity, could you please define what you mean by lump rate? If you make people on the first $x of income, you can offset it by increasing the tax rate on income after the first $x.

So your counter argument is that our system is good enough, so it doesn't matter? Why wouldn't you want the best tax system possible? I listed a fairness property that all tiered tax systems violate, but which a flat tax + lump sum transfer does not. What advantage does the tiered tax system have over the flat tax + lump sum transfer?

Also, how does one derive a unique optimal progressive tax system based on accepted axioms and empirical data? It is possible to do this using a flat tax + lump sum transfer.

I already gave some downsides. See posts 139 and 163. For example, it fails the fairness property that I was referring to with the fishermen example.

... That's basically what we have right now...

You can imagine that they both retire after the 2 years if it helps. And the second fisherman didn't receive a promotion; he was just unlucky in the first year and lucky in the second year. You can easily extend my fisherman scenario to a scenario of any finite length of time. Let's say the two fishermen earn the same amount of money over their entire lifetimes, but one fisherman has more variation in annual income than the other fisherman. The fisherman with more variation in annual income pays more tax in a 'progressive' tax system. Except it can't... Do you want me to provide a mathematical proof? Who is advocating charging the fishermen a lump sum? Yes, but you can simultaneously increase the tax rate such that the end result is revenue neutral.

Small != insignificant. But continue misrepresenting me if you want. Also you are confusing a claim about future climate change with a claim about what caused past climate change.

I never claimed that 30 W/m^2 oscillations in solar insolation would bias estimates of temperature changes (which wouldn't make sense given you just have oscillations, which have an expected value of zero). My claim was that it makes the estimates and the results from CMIP5 models less reliable. But if you purposely wish to confuse claims about something biasing an estimate with claims about an estimate being less reliable then that is your choice.

The fact that solar irradiance will decrease is being ignored, yes. Yes, and this assumption is dumb. Edit: I'll try to quantify the magnitude of ignoring this effect for you. The difference in TSI from the Mauder Minimum to the 2013 is ~1.3 W/m^2. If we divide this by 4pi to average chance in solar insolation and use a sensitivity of 0.75 K/W*m^2 (the sensitivity value that Hansen seems to love; I strongly disagree with it, but you seem to like Hansen and you need sensitivities this high to get the high ECS estimates of the climate models) then this gives a temperature difference of up to 0.078 C. I will also point out that Mann et al. reconstructed temperatures (the ones that TimG doesn't like) suggest that the Medieval Warm period - Little Ice Age global temperature difference was ~0.2 C.

Whether an estimate is unbiased or not has a clear mathematical definition; the expected value of the parameter is equal to the estimate of the parameter. In the case of volcanic aerosols, the expected effect on temperatures is negative, thus excluding the expected effect of volcanic aerosols from an estimate means that the estimate is omitting a negative expected value, so it will overestimate future warming and the estimate does not satisfy the definition of being unbiased. I'll even try to quantify this for you. Mean aerosol optical thickness at 550 nm from 1850-2012 is ~0.0127 (http://data.giss.nasa.gov/modelforce/strataer/). Due to Pinutubo, there was a global cooling of ~ 0.5 C from 1991-1993 (https://en.wikipedia.org/wiki/Mount_Pinatubo). The mean aerosol optical thickness for 1991-1993 was 0.0747. Given that equilibrium temperature change is roughly a linear function of aerosol optical depth, this suggests that the expected cooling due to volcanic eruptions should be ~0.085 C. So the assumption that volcanic activity will cease results in overestimating future temperature by ~0.085 C.

It's called only using the limited information provided in this thread and being too lazy to go to AR5 to verify your obscure claim (at least initially), when that burden should be on you.

And if the models are overestimating the effect of aerosols (and thus simultaneously the effect of greenhouse gases), then their models will be oversensitive and will overestimate the proportion of anthropogenic warming. Rescaling the model results to match observations will not change this proportion. Thus even after rescaling, the proportion of anthropogenic warming will be overestimated. You can see this oversensitivity even after rescaling in the difference between model and observations post 2000 (figure 10.1 a), and the large divergence between model predictions and observations (figure 11.9).

The first one should say expected to decrease, not increase. Sorry, I made a mistake. Thank you for pointing it out. I have corrected it. I'm still affected by that. One of my symptoms is a higher rate of typos.

You don't understand what I mean by 30 W/m^2 zonal oscillations nor the basics of the paper I linked to? I guess I can dumb things down for the less scientifically literate. CMIP5 computer models have to use the angle of the sun in order to calculate the solar insolation (i.e. amount of direct sunlight in W/m^2) of a specific location on Earth. Due to sampling error, sometimes two places at the same latitude but different longitude will be calculated to have different levels of solar insolation (i.e. zonal oscillations). The extra variation in solar insolation due to this error can be as high as 30 W/m^2, which is much higher than the increase in solar irradiance since the Mauder Minimum (TSI increased by ~1.4 W/m^2 from Mauder minimum to the 1950's, but you should divide by ~4pi to get ~0.1 W/m^2 of solar insolation change).

Flat tax + lump sum transfer also satisfies this fairness property (the two fishermen would have the same disposable income after 2 years): Where as the overly complicated tiered progressive tax system we have does not.

Wow cyber. I like how you continue to refuse to provide an adequate definition of a progressive tax system. I guess it is whatever you subjectively feel. Claiming that a flat tax disproportionately affects the poor, when the proportion of tax is the same for anything doesn't make sense. Perhaps you should have said that is undesirable. You also ignored my comment about flat tax + lump sum transfer. You think that a flat tax on it's own is inadequate? Well I agree with you, which is why you should combine it with a lump sum transfer. For example, give every Canadian an annual lump sum transfer to help them obtain the essentials, and tax what people make at a flat tax. For example, if the transfer were $20,000 and the flat tax were 30% then a person's annual disposable income would be $20,000 + 0.7*I, where I is their annual income. This would greatly simplify the tax system and you can get rid of all the loopholes, tax credits, welfare, minimum wage, etc.