David Ricardo was an English

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 political economist

Political economy

Political economy originally was the term for studying production, buying, and selling, and their relations with law, custom, and government, as well as with the distribution of national income and wealth, including through the budget process. Political economy originated in moral philosophy...

, often credited with systematising economics, and was one of the most influential of the classical economist

Classical economics

Classical economics is widely regarded as the first modern school of economic thought. Its major developers include Adam Smith, Jean-Baptiste Say, David Ricardo, Thomas Malthus and John Stuart Mill....

s, along with Thomas Malthus

Thomas Malthus

The Reverend Thomas Robert Malthus FRS was an English scholar, influential in political economy and demography. Malthus popularized the economic theory of rent....

, Adam Smith

Adam Smith

Adam Smith was a Scottish social philosopher and a pioneer of political economy. One of the key figures of the Scottish Enlightenment, Smith is the author of The Theory of Moral Sentiments and An Inquiry into the Nature and Causes of the Wealth of Nations...

, and John Stuart Mill

John Stuart Mill

John Stuart Mill was a British philosopher, economist and civil servant. An influential contributor to social theory, political theory, and political economy, his conception of liberty justified the freedom of the individual in opposition to unlimited state control. He was a proponent of...

. He was also a member of Parliament

Parliament

A parliament is a legislature, especially in those countries whose system of government is based on the Westminster system modeled after that of the United Kingdom. The name is derived from the French , the action of parler : a parlement is a discussion. The term came to mean a meeting at which...

, businessman, financier

Financier

Financier is a term for a person who handles typically large sums of money, usually involving money lending, financing projects, large-scale investing, or large-scale money management. The term is French, and derives from finance or payment...

 and speculator, who amassed a considerable personal fortune. Perhaps his most important contribution was the law of comparative advantage

Comparative advantage

In economics, the law of comparative advantage says that two countries will both gain from trade if, in the absence of trade, they have different relative costs for producing the same goods...

, a fundamental argument in favour of free trade

Free trade

Under a free trade policy, prices emerge from supply and demand, and are the sole determinant of resource allocation. 'Free' trade differs from other forms of trade policy where the allocation of goods and services among trading countries are determined by price strategies that may differ from...

 among countries and of specialisation among individuals.