This is often advocated by Green parties, which often mix socialist ideas of economic equality with a desire to implement this equality in a decentralized manner. It was also advocated by Nobel laureate economists Herbert Simon and James Tobin. One widely accepted consequence of this policy is that there are less two-income households. Advocates consider this a benefit of the Basic Income, whereas critics consider this a problem. Much more information about basic income is available at the website of the Citizens' Income Trust, http://www.citizensincome.org. (Note: It has been reported that that page does not show correctly in mozilla. It works in links however, after pressing \\).
Different groups advocating such policies suggest different means by which it may be provided.
There are several advantages to this scheme, and several disadvantages.
Basic income would help people in scenarios such as:
Self-employment. People who are self-employed would not risk their entire income, they could have a business if it made any profit at all.
Individuals, possibly self employed, who needed an assistant and could not pay them full rate during training. The assistant could then live on basic income. This would create many low-paid part-time jobs.
People who wish to help community (eg. open-source programmers) could do so full-time without worrying about income. In fact, there would be pay levels from zero (voluntary) to very high (unpleasant jobs).
Nobody would be forced to do low-paid unpleasant jobs because they could not survive otherwise. The pay levels of these jobs would rise considerably, and the unemployed would have more bargaining power instead of being at the mercy of their potential employers.
There are several large disadvantages however, two of which might bring the entire scheme down.
One of those is cost. Cost would necessarily be extremely high, and if that cost were collected from taxes, tax levels would increase significantly, which creates a disincentive to work. This brings us to the other point. If people are not motivated to work after the introduction of BI, there would be a period of restructuring during which there could be a crisis with nobody willing to work, and hence nobody paying taxes. These problems can be resolved only by changing the taxation system and introducing BI slowly, over several years.
Sources: Tony Walter (1989) Basic Income, Freedom from Poverty, Freedom to Work
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