Is rationalism really the foundation of modern secularism? (By Isaac Shim)

A prominent philosophical perspective in contemporary religious thinking is secularism. Secularism, by definition, advocates for the clear separation between religion and the state, ensuring that the state doesn’t discriminate or show bias toward any religion and instead remains neutral. Some claim that this principle is derived from another school of thought known as rationalism. Rationalism is a method of investigating and understanding the world through reason and evidence, rather than relying on emotional instincts or religious values. Is rationalism the foundation of modern secularism? To answer this question, we must first compare the two principles.

An oversimplification of both philosophies might lead someone to think they are quite similar. Both value the capacity of the human mind and, in a sense, challenge traditional religious authority. They also emphasize scientific reasoning and prioritize evidence-based thinking. However, there are significant differences at the core of these philosophies.

The first important difference lies in the main aims of these philosophies. Rationalism does not necessarily advocate for the separation of, or directly oppose, religious institutions. Emerging during the Enlightenment, rationalism focuses on acquiring knowledge through evidence, scientific reasoning, and logic rather than relying on instinct or faith. Secularism, however, is concerned with the relationship between government and religion, advocating for a clear separation between the two.

The second key difference lies in the core nature of each concept. Rationalism can be viewed as a method of investigation or a doctrine—a way to explore and acquire knowledge, primarily through reason and evidence. It is an intellectual tool for understanding the world. Secularism, however, is a belief system and a political philosophy. It advocates for the separation of government and religion. While rationalism doesn't necessarily call for policy changes or opposition to anything specific, it is a way of thinking that intersects with various other philosophies. This distinction explains why rationalism is applied in fields like science and mathematics, while secularism pertains to law and governance. Secularism seeks neutrality, whereas rationalism is focused on theory and understanding reality.

That doesn’t mean they lack similarities, though. Rationalism and secularism both share roots in the Enlightenment, which is why they place a strong emphasis on theory and reasoning. Both philosophies champion individualism—whether it’s the individual's freedom of religious expression or their capacity for independent reasoning. Additionally, they both prioritize critical thinking and, in some ways, resist the influence of religion on the issues they address. Both can also be viewed as part of the broader philosophy of humanism, which emphasizes the significance and potential of human beings over divine authority.

What’s essential is that both of these ideas are nuanced and complex in their own ways, and it would be an oversimplification to claim that one has directly caused the other. Supporting these philosophies does not require being nonreligious. For example, you can be a devout Catholic and still believe that the Pope should have no involvement in America’s governmental affairs. Similarly, you can practice Islam while valuing physical evidence and logical reasoning above all else. It’s also possible to support either rationalism or secularism individually, or even both. By investigating these two philosophies, one can see that while they share Enlightenment roots and may be related, rationalism and secularism have developed along distinct paths and should be treated as separate philosophical entities.