Laffer curve costs). Although tax policy is often mentioned in relation to supply-side economics, supply-side economists are concerned with all impediments to the supply of goods and services and not just taxation. In their economics textbook "Principles of Economics" (7th edition), economists Karl E. Case of Wellesley College and Ray Fair of Yale University stated "The Laffer curve shows the relationship between tax rates and tax revenues. Supply-side economists use it to argue that it is possible to generate higher revenues by cutting tax rates, but evidence does not appear to support this. The lower tax rates by the Reagan administration decreased
From each according to his ability, to each according to his needs can be found in the Guilford Covenant in 1639: Some scholars trace the origin of the phrase to the New Testament. In Acts of the Apostles the lifestyle of the community of believers in Jerusalem is described as communal (without individual possession), and uses the phrase ""distribution was made unto every man according as he had need"" (): However, other scholars disagree with this, and claim that the phrase 'from each according to their abilities, to each according to their needs' has a non-religious origin, in 'the Roman legal concept of obligation in solidum' The Roman legal concept of obligation