The Rationalist movement has some similarities in ideology and intent to the humanist and atheist movements, i.e. it aims to provide a framework for social and philosophical discourse outside of religious or supernatural beliefs.

Modern rationalism has more in common with secular humanism than other strands of humanism. While the broader humanist movement tends to seek common moral and ethical grounds with many religions, there is a much stronger atheistic influence in modern rationalism. However, not all rationalists are atheistic, and there is a greater compatibility with agnosticism. Many rationalists regard themselves as 'freethinkers', and outside of the human-centred focus of humanism and mainstream religions. In this regard, some rationalists consider there is no reason to rate humans as more important than other animals.

During the middle of the twentieth century there was a strong tradition of organised rationalism, which was particularly influenced by British intellectuals such as Bertrand Russell.

Modern rationalism has little in common with the historical philosophy of Continental Rationalism expounded by Descartes. Indeed, a reliance on empirical science is often considered a hallmark of modern rationalism, whereas continental rationalism rejected empiricism entirely.

See also: atheism, agnosticism, freethought, skepticism

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