Dennis Rasmussen’s The Infidel and the Professor explores the relationship of Adam Smith and David Hume to teach us about the value of human rights, morality, and freedom of thought.

The Scottish Enlightenment was a shift in political and economic thought that eventually led to the institutional abolition of slavery, legal equality of humans, individualism, and free trade. It essentially led to all the values that made the West a cradle of democracy and restrained governance. There are a lot of great books on the Scottish Enlightenment, but if you want a narrative that explains major ideas as they relate to the lives of great thinkers, grab a copy of The Infidel and the Professor by Dennis Rasmussen.

The Infidel and the Professor

The Infidel and the Professor covers some of the most important ideas and developments of the Scottish Enlightenment, but it is written with a focus on the relationship of Adam Smith and David Hume. The story of these two iconic Scotsmen is written in such a way that is extremely informative without being pedantic. The author’s pleasant writing style is a nice touch, but the true value is the relevance of Smith’s and Hume’s ideas. I will cover what I thought were the most important ideas here, but be sure to read Rasmussen’s work. You’re cheating yourself if you don’t.

Hume’s Opposition to Factions

Many of our modern problems are caused by divisive politics and conflicts of loyalty. For example, consider the two-party system in the United States. Policies are often rejected purely on the grounds of making a statement. A representative votes against a spending bill purely to spite the opposing party. In retaliation, the members of that opposing party decide to vote against future bills sponsored by the other party. This cycle continues, and the country becomes more divided over time.

This political division may seem like a 21st century trend, but the great philosopher David Hume predicted it way back in the 18th century. Hume was a fierce critic of factions, also known as parties and interest groups. Through his impressive reasoning skills, Hume understood that a society with powerful special interests would eventually become divided as citizens turn against their neighbors due to differing politics.

There are no clear solutions to special interests and party divisions in modern society, but acknowledging Hume’s warning is a good first step.

Smith and Hume on Free Thought

David Hume and Adam Smith were well-known for their commitment to thinking freely. Both men tended to oppose the common beliefs of Scotland in their day. Because of their critical analysis of the world, neither Smith nor Hume succumbed to group think.


Smith and Hume had the courage to suggest religious reforms to oppose fanaticism. Hume was a skeptic, an agnostic who sought out any opportunity to ridicule the Church. Smith was quiet about his reverence, but it seems likely that he was also a skeptic (albeit a gentler one than Hume). Surprising everyone, Hume proposed a creative solution to religious intolerance. To curb fanaticism, Hume suggested that the state should sponsor a tolerant religion to prevent fanatic competition between opposing clergy. He argues that a state-subsidized religious sect would eliminate more radical forms of religion that could not compete due to a lack of funds.

Smith demonstrates that, while Hume was his dear friend, it is necessary to speak up when a strong personality suggests something that is not correct. Smith argued that state-sponsored religion would not deter fanaticism. Instead, it would encourage extremism. He argued that, in a society with a state-sponsored religion, religious groups without state subsidies would need to find alternative ways to attract followers. Smith believed that religious minorities may do this through fanaticism and radical narratives. In addition, the state religion would use the coercive power of the government to snuff out political rivals. I refer you to the Spanish Inquisition if you don’t buy his logic. To prevent this tyranny, Smith proposed a separation of church and state. Without state interference, religions would compete for followers, and each church would the check the power of others. This results in declining fanaticism and greater freedom in society.

Religion and policy are like fire and oil; they should never mix. The best societies have secular governments and the freedom to choose private religions. It would serve us well to remember that.


The governments of the 21st century have developed an unhealthy habit of protecting dying industries that would otherwise fall by the wayside. While this may ensure the jobs of workers for a short period of time, consumers are left with more expensive options and people develop a habit of lobbying for government intervention whenever markets favor a competitor.

Just as Hume warned against factions, Smith signaled the alarm about protectionism well before the 21st century. In his iconic book The Wealth of Nations, Adam Smith warned against mercantilism, the protectionist system that discouraged trade and market forces in favor of gold accumulation. This system concentrated power and wealth on political elites and their friends while the majority of society suffered under poor conditions. To eliminate this imbalance of power, Smith proposed a system of free trade that would interrupt the accumulation of power by elites. Smith’s proposal was a direct attack of mercantilism and colonialism. It was arguably the greatest instance of free thought in the past 300 years.

Adam Smith receives most of the credit for free market economics in universities across the world today, but we must not forget the role of David Hume. Hume included many advantages of unfettered markets in his massive text The History of England years before The Wealth of Nations was published. Does this mean that Smith is unoriginal? Not at all. Hume offers a black-and-white view of markets while Smith offers a comprehensive discussion that offers both the strengths and weaknesses of a commercial society. For example, while Hume views work as part of the joys of life, Smith has a more pessimistic view. While work is necessary to obtain material well-being, it comes at the cost of anxiety. He goes on to argue that happiness in a commercial society exists only if we equate well-being to material wealth.

Are you depressed yet? No? Maybe this will help. Adam Smith even critiqued the division of labor, arguing that while it is economically efficient, causes people to sacrifice their “intellectual, social, and martial virtues”. Despite these critiques of basic economic principles, Adam Smith believed that capitalism is far superior to the inequality of aristocracy and political favoritism. I tend to agree.


While Smith and Hume attacked the political and economic machine of mercantile Europe, they seemed to avoid a significant uproar from the establishment. This was not the case when they critiqued morality. The nature of morality is an important topic that allows us to understand altruism and other good behaviors, so everyone can benefit from the views of Hume and Smith.

Their argument is based on the claim that morality does not come from a deity. This was not a new claim; philosophers before Smith and Hume argued that moral behavior came from logic and reason. Smith and Hume didn’t buy this argument either, so they proposed an alternative. Instead of divinity or reason, sympathy is the root of morality. But as Hume and Smith normally do, they debated on the functions of sympathy. Hume offered a practical approach that deals with human emotions and expressions. He argued that humans are sympathetic creatures who generally do not enjoy causing pain, so we avoid behaviors that result in expressions of pain, sadness, or discomfort.

[Note: If Hume’s theory of morality is true, it may shed some light on why our digital worlds are so divided. People on the Internet cannot see the expressions of the people they are talking with, so sympathy does not regulate morals in cyberspace.]

Smith agreed that expressions play a role in the regulation of morals, but he took the theory a step further. In his Theory of Moral Sentiments, Adam Smith argued that moral behavior comes from empathy. We imagine ourselves in another person’s situation to understand their perspective. We would not wish harm on ourselves, so we tend to avoid actions that cause others discomfort. In Smith’s view, people who lack empathy will behave without morals. By returning to this view of morality, we can create a freer society that is more peaceful and cooperative. I think we can all agree that such a society would be appreciated in the modern world.

The Next Enlightenment

The ideas of Adam Smith and David Hume did not simply come into existence by some accident or miracle. They were the result of support and criticism for the ideas of Locke, Hobbes, Plato, Zeno, Aristotle, Augustine, Cato, and a multitude of other thinkers. To build the future, we must not forget the ideas of the past. Isaac Newton once said that his discoveries would not be possible without returning to the ideas of those who came before him. He was standing on the shoulders of giants. We have a similar opportunity. By thinking critically about the ideas of the Scottish Enlightenment, we may find a path to a free and peaceful future. The responsibility rests with all of us.