The certainty of what each individual ought to pay is, in taxation, a matter of so great importance, that a very considerable degree of inequality, it appears, I believe, from the experience of all nations, is not near so great an evil as a very small degree of uncertainty.
 Adam Smith, The Wealth of Nations (1776). copy citation

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Author Adam Smith
Source The Wealth of Nations
Topic importance inequality
Date 1776
Language English
Reference An Inquiry into the Nature and Causes of the Wealth of Nations
Note
Weblink http://www.gutenberg.org/files/3300/3300-h/3300-h.htm

Context

“Where it is otherwise, every person subject to the tax is put more or less in the power of the tax-gatherer, who can either aggravate the tax upon any obnoxious contributor, or extort, by the terror of such aggravation, some present or perquisite to himself. The uncertainty of taxation encourages the insolence, and favours the corruption, of an order of men who are naturally unpopular, even where they are neither insolent nor corrupt. The certainty of what each individual ought to pay is, in taxation, a matter of so great importance, that a very considerable degree of inequality, it appears, I believe, from the experience of all nations, is not near so great an evil as a very small degree of uncertainty. 3. Every tax ought to be levied at the time, or in the manner, in which it is most likely to be convenient for the contributor to pay it. A tax upon the rent of land or of houses, payable at the same term at which such rents are usually paid, is levied at the time when it is most likely to be convenient for the contributor to pay; or when he is most likely to have wherewithall to pay.” source