脊髓
稅(tax)
政府向人民、團體、或商業機構徵募之款項。納稅是納稅人的共同義務，不以求取其他利益回報作為交換。稅自古代即已存在，例如古羅馬即有著名的財產稅和商業稅，不過對於當時的國家歲收，關稅（tariff）比國內稅更重要。但是現代經濟則出現相反的趨勢，國家歲收絕大部分都是以國內稅為主，並且逐步廢除關稅。稅有三種主要功能：支付政府的花費；維持經濟成長的穩定；減緩所得及財富分配的不公平。稅也可能用於非財政的理由，例如鼓勵或不鼓勵某些活動（例如香菸消費稅）。稅可分為直接稅與間接稅，直接稅指的是納稅人不能轉移給他人的稅；主要是以人為物件的稅、且是以個體的能力為基礎來課微，依據納稅人的收入或財富而徵收。直接稅包括所得稅、淨值稅（net worth）、死亡稅（包括遺產稅和資產稅）、贈與稅等。間接稅指的是可以全部或部分轉移給非法定納稅人的稅。間接稅包括貨物稅、銷售稅、加值稅（value-added taxes）等。稅也可根據其對財富分配的效果而分類，例如對所有納稅人都課以同樣相對負擔之比例稅（proportional tax），另外還有累進稅（progressive taxes）和累退稅（regressive taxes）。
English version：
tax
Government levy on persons,groups,or businesses. Taxes are a general obligation of taxpayers and are not paid in exchange for any specific benefit. They have existed since ancient times—property taxes and sales taxes were known in Rome—but tariffs were favored over internal taxes as a source of revenue. In modern economies,there has been a trend away from tariffs in favor of internal taxes,which provide the majority of revenues. Taxes have three functions: to cover government spending,to promote stable economic growth,and to lessen inequalities in the distribution of income and wealth. They have also been used for nonfiscal reasons,such as to encourage or discourage certain activities (e.g.,cigarette consumption). Taxes may be classified as direct or indirect. Direct taxes are those that the taxpayer cannot shift onto someone else; they are mainly taxes on persons and are based on an individual's ability to pay as measured by income or net wealth. Direct taxes include income taxes,taxes on net worth,death duties (i.e.,inheritance and estate taxes),and gift taxes. Indirect taxes are those that can be shifted in whole or in part to someone other than the person legally responsible for payment. These include excise taxes,sales taxes,and value-added taxes. Taxes may also be classified according to the effect they have on the distribution of wealth. A proportional tax is one that imposes the same relative burden on all taxpayers,unlike progressive taxes and regressive taxes.