Natural Law Theory: Crash Course Philosophy #34

Thomas Aquinas, the 13th-century Italian Dominican friar and theological superstar, wrestled with a profound moral dilemma: How can people follow God’s moral rules (divine commands) if they have never heard of God or read scripture? Aquinas concluded that a loving God would not expect humanity to follow rules without providing a built-in mechanism to discover them. This foundational premise birthed Natural Law Theory, one of the most influential and enduring ethical frameworks in Western history.

1. The Core Premise: A Purpose-Driven Universe

Aquinas viewed the cosmos as an orderly, predictable, and purpose-driven system designed by a magnificent Creator. In this teleological (goal-oriented) universe, everything has a specific function and natural design.

• Sunlight and Water: Designed naturally to nourish and sustain plants.
• Meat: Designed to nourish carnivores like cats.
• Plants: Designed to nourish herbivores like rabbits.

Because God created humans with intentional design, He hardwired us with an innate sense—an internal compass—to recognize the things we are designed to seek. These fundamental goals are known as the Basic Goods.

2. The Seven Basic Goods

According to Aquinas, human beings share specific natural inclinations with other creatures, alongside distinctively rational inclinations. From these inclinations, we derive seven core Basic Goods that define human flourishing:

Breakdown of the Basic Goods:

1. Self-Preservation: Just like animals, humans possess an innate survival instinct. We naturally avoid dangerous situations (like swimming with hungry sharks) without needing prolonged philosophical calculation.
2. Reproduction: While some organisms reproduce independently, humans require cooperation. God intentionally made reproduction pleasurable to ensure species survival.
3. Educating Offspring: Bringing children into the world is not enough; nurturing and educating them is essential so they can survive, learn morality, and eventually reproduce themselves.
4. Seeking God: Humans possess an innate drive to seek the divine, regardless of formal religious exposure.
   • Existentialist parallel: Even the atheist philosopher Jean-Paul Sartre agreed that humans are born with a "God-shaped vacuum" in their hearts.
5. Living in Society: Following Aristotle, Aquinas recognized humans as inherently social animals. We thrive in communities and experience deep psychological needs for love, acceptance, and belonging.
6. Avoiding Offense: Because we desire group inclusion, human nature compels us to avoid behaviors that turn our community against us (the natural basis for social guilt and shame).
7. Shunning Ignorance / Pursuing Knowledge: Driven by curiosity, humans seek truth and understanding. This trait promotes survival, as ignorance can easily lead to a fatal end.

3. Deriving Natural Law from Basic Goods

We do not need a Bible, a church, or formal religious education to deduce Natural Law.

• Observation + Reason: Our natural instincts reveal the Basic Goods, and human reason allows us to derive moral laws from them.
• The Moral Rule: An action is morally right if it aligns with Natural Law and supports human flourishing.

How Natural Law Generates Rules:

Reason takes a Basic Good and generates both negative prohibitions (what not to do) and positive injunctions (what to do):

Note on Church Doctrine: The prohibition against frustrating reproduction directly explains why the Catholic Church traditionally opposes artificial contraception: it severs the reproductive act from its natural, God-given biological purpose.

4. Why Do People Violate Natural Law?

If Natural Law is self-evident and hardwired into our very biology, why do humans constantly violate it? Aquinas offered two primary explanations:

1. Ignorance: Humans sometimes pursue what they mistakenly believe is good because they are simply ignorant.
   • Real-World Example: Historically, doctors once recommended cigarette smoking. People thought they were supporting their health, but they were actually destroying it.
2. Emotions Overriding Reason: Following Aristotle, Aquinas noted that humans are both rational and emotional creatures. Even when we know the right thing to do, intense emotions and desires can overpower our rational minds.

5. Criticisms of Natural Law Theory

While Natural Law Theory grounds morality in human flourishing and provides objective reasons to be good, it faces substantial philosophical pushback.

A. The Secular Problem

Like Divine Command Theory, Natural Law Theory is unconvincing to those who do not accept its foundational premise. If an individual rejects the existence of a Creator who designed the universe with purposeful intent, the entire architecture of Natural Law collapses.

B. Hume’s "Is-Ought" Problem

The 18th-century Scottish philosopher David Hume exposed a critical logical flaw known as the "Is-Ought" Fallacy (or the problem of the ought).

• The Fallacy: Natural Law Theory assumes that because something is a certain way in nature, it ought to be that way morally.
• Critique: Observing nature reveals that living creatures have a strong survival instinct, but that does not automatically make survival a moral absolute in every context.
  • Example: Extreme survival instincts can drive people to commit horrific acts (e.g., pushing someone into a freezing storm to scavenge their resources). Similarly, observing a biological drive for sex does not mean every sexual impulse is moral, nor does it render choosing a childfree life "unnatural" or immoral.

Summary and Key Takeaways

• Thomas Aquinas's Vision: Argued that God equipped all humanity with built-in tools to recognize moral rules, independent of scripture.
• Teleological Universe: The cosmos is purposeful and predictable; every creature and object has an intentional design and function.
• The Seven Basic Goods: Comprise self-preservation, reproduction, educating offspring, seeking God, living in society, avoiding social offense, and pursuing knowledge.
• Deriving Morality: Human reason uses these Basic Goods to derive specific moral prohibitions and positive commands.
• The Role of Reason: Actions are morally correct when they align with our natural design and foster human flourishing.
• Failures of Morality: Violations of Natural Law stem from human ignorance or emotions overpowering reason.
• Hume's Critique: David Hume criticized the theory for committing the "Is-Ought" fallacy—mistakenly jumping from descriptive facts about nature to prescriptive moral rules.