The Problem of Fact and Value Judgment: Natural Laws and Moral Principles, Is and Ought

Immanuel Kant, who revolutionized 18th-century modern philosophy, explored “What can we know?” and “What ought we to do?” in his works 'Critique of Pure Reason' and 'Critique of Practical Reason'. These mark the modern beginnings of epistemology and ethics.

What I want to highlight here isn’t Kant’s specific arguments but why it’s crucial to distinguish between natural laws and moral principles.

Natural laws explain the phenomena of nature. For instance, they help us understand and predict that gravity pulls objects downward, but they don’t dictate human behavior.

Moral principles, on the other hand, guide human actions and value judgments. Encompassing ethical values like justice, human rights, and fairness, they play a key role in building a better society.

In short, natural laws (the “is”) are tools for understanding the world, while moral principles (the “ought”) guide us in upholding human dignity and constructing society.

[The Naturalistic Fallacy and the Moralistic Fallacy]

It seems more people these days are aware of the naturalistic fallacy (deriving an “ought” from an “is”) and the moralistic fallacy (applying moral standards to nature). These concepts often come up in fields like evolutionary biology, so let’s break them down with an example.

In nature, infanticide can be observed under certain conditions (e.g., resource scarcity). Analyzing this to uncover the mechanisms at play doesn’t mean infanticide is justified. Claiming it is commits the naturalistic fallacy. Eugenics is a prime historical example of this error, leaving a painful legacy by discriminating against lives based on biological superiority.

Conversely, judging whether an animal that commits infanticide in nature is morally wrong is also flawed. This is the moralistic fallacy—moral principles don’t exist in nature; they’re created by humans for societal needs.

People with certain ideologies often fall into these traps. For instance, some discuss biological differences between men and women (like hormones or physical structure) and then justify gender roles. This derails the debate, making it emotional and unproductive.

I believe distinguishing between “is” and “ought” is the key to reducing such confusion and fostering better discussions. If science and ethics fail to find balance, what new tragedies might we face? Can this distinction truly be the foundation for a better society?