The Ricardian vice refers to abstract modelbuilding and mathematical formulas with unrealistic assumptions. In simpler terms, the Ricardian vice is the tendency for economists to make and test theories that aren't troubled by the complexities of reality, resulting in theories that are mathematically beautiful but largely useless for practical applications. The Ricardian vice is prevalent in economics and is named after David Ricardo, one of the first economists to bring mathematical rigor to the discipline.
David Ricardo came up with many useful theories and laws that defended free trade and sound monetary policies, including them the law of comparative advantage and the law of diminishing returns. As time passed, however, Ricardo depended more and more on modelbuilding and large (sometimes erroneous) assumptions to achieve the results he wished.
For example, Ricardo focused on the distribution of income rather than the growth of economic activity to "prove" that everyone but landlords was doomed to subsistence wages. He also spent time seeking an ironclad measure of value, trying to link it to the cost of labor while calculating out any benefits of machine labor. Even in his law of diminishing returns, Ricardo simplified all agricultural crops into one field all farmed with the same technique and having an equal yield on all sections. Adding to these already sizable assumptions, he factored the cost of wages as being equal to the subsistence level that he believed to be unavoidable. While it yielded a result that showed that tariffs harm the domestic economy, it oversimplified the case.
Even today, many economic models mathematically remove, simplify, or fix dynamic components like competition with an arbitrary value. While these exercises in pure deductive reasoning can yield useful clues about how things might work, they need to be held against the way things actually work to have any value.
For more insight, read How Influential Economists Changed Our History.

What does the Ricardian Equivalence say about budget deficits?
Find out what the theory of Ricardian equivalence says about the impact of government deficit spending on aggregate demand ... Read Answer >> 
Why aren't economists rich?
"If you're so smart, how come you're not rich?" is a question that economists seem to invite. If they can explain the intricacies ... Read Answer >> 
What are specialization and comparative advantage in international trade?
Take a closer look at David Ricardo's revolutionary insight about specialization and comparative advantage and the benefits ... Read Answer >> 
Which of the following statements most accurately describes the impact of an expansionary ...
The correct answer is: b) The foundation of this model is the "Ricardian equivalence", which states that an expansionary ... Read Answer >> 
Why do economists build assumptions into their economic models?
Find out why economists use unrealistic assumptions in their models to apply a version of the scientific method and make ... Read Answer >> 
What is the chaos theory?
The chaos theory is a complicated and disputed mathematical theory that seeks to explain the effect of seemingly insignificant ... Read Answer >>

Trading
7 Controversial Investing Theories
We take a closer look at the theories that attempt to explain and influence the market. 
Markets
The History Of Economic Thought
Economics is a vital part of every day life. Discover the major players who shaped its development. 
Trading
Understanding the BlackScholes Model
The BlackScholes model is a mathematical model of a financial market. From it, the BlackScholes formula was derived. The introduction of the formula in 1973 by three economists led to rapid ... 
Managing Wealth
Using Normal Distribution Formula To Optimize Your Portfolio
Normal or bell curve distribution can be used in portfolio theory to help portfolio managers maximize return and minimize risk. 
Trading
Modern Portfolio Theory vs. Behavioral Finance
Modern portfolio theory and behavioral finance represent differing schools of thought that attempt to explain investor behavior. Perhaps the easiest way to think about their arguments and positions ... 
Trading
Manipulating Facts to Fit a Theory: A Dangerous Trading Practice
This practice is common with experienced and new traders, and it can lead to huge losses. Find out how to avoid it. 
Markets
Why Can't Economists Agree?
There are many reasons why economists can be given the same data and come up with entirely different conclusions. 
Managing Wealth
Quantitative Analyst: Career Path & Qualifications
Learn about the work that quantitative financial analysts do everyday, and determine what it takes to become a successful professional in the field. 
Trading
Dow Theory: Current Relevance
By Chad Langager and Casey Murphy, senior analyst of ChartAdvisor.comThere is little doubt that Dow theory is of major importance in the history of technical analysis. Many of its tenets and ... 
Markets
Law Of Diminishing Marginal Utility
Learn about this law of economics related to consumption.

David Ricardo
A classical economist known for his Iron Law of Wages, labor ... 
Ricardian Equivalence
An economic theory that suggests that when a government tries ... 
Mathematical Economics
Mathematical economics is a discipline of economics that utilizes ... 
Law of Diminishing Marginal Returns
A law of economics stating that, as the number of new employees ... 
Economic Stimulus
Attempts by governments or government agencies to financially ... 
Classical Growth Theory
A theory on economic growth that argues that economic growth ...