been embodied by Adam Smith in four maxims or principles, which, having been generally concurred in by subsequent writers, may be said to have become [pg 538] classical, and this chapter can not be better commenced than by quoting them:336
“1. The subjects of every state ought to contribute to the support of the government, as nearly as possible in proportion to their respective abilities: that is, in proportion to the revenue which they respectively enjoy under the protection of the state. In the observation or neglect of this maxim consists what is called the equality or inequality of taxation.
“2. The tax which each individual is bound to pay ought to be certain, and not arbitrary. The time of payment, the manner of payment, the quantity to be paid, ought all to be clear and plain to the contributor, and to every other person. The certainty of what each individual ought to pay is, in taxation, a matter of so great