Hume's law is that "No testimony is sufficient to establish a miracle, unless the testimony is of such a nature that its falsity is more miraculous than the fact which it seeks to establish."

Hume in In the last "Appendix" of the first section of the first chapter of the third volume of his "Treatise of Human Nature", he reminds people to pay attention: when deducing "should" from "is", one must be careful and must reason strictly. In other words, Hume expressed doubts about the fact that people often arbitrarily deduce "should" from "is", and believed that this was a major issue involving the system of ethics.

So, Hume raised a major question involving the ethical system: whether "should" can be derived from "is". This is the "Hume problem" (Hume's problem). Hume himself did not give an answer to this question, just like his philosophical skepticism (agnosticism).

The question Hume raised here provides ethics with a basic rule for reasoning from factual judgments to moral judgments, that is, the conclusion of a moral judgment cannot be deduced from a factual judgment. Hale was convinced of the validity of this rule and called it "Hume's law."

To put it simply, this law is: we cannot deduce "ought" from "is". In 1903, Moore, the modern British philosopher and founder of metaethics, proposed the famous "naturalistic fallacy" in his book "Principles of Ethics". He calls any ethics that uses "something that exists" to define "good" a naturalistic error.

Academic circles usually express the naturalistic fallacy simply as: any attempt to deduce "should" from "is" is committing the naturalistic fallacy. Extended information

Hume's problem contains three elements: fact, desire, and ought. Facts are only external conditions that stimulate people's original desires or generate new desires. Facts cannot deduce desires, nor should they be derived. Shoulds can be derived from desires.

But the wish itself has another basis in fact. The West generally defines value as subjective or transcendental, which is superficial. Values ??also have a basis in fact. However, among two or more "desires (shoulds)", which one is "more deserving" has no factual basis.

It can only depend on the intensity of a person’s desire or reason and will. The significance of Hume's law lies in enlightenment to discover more objective moral inevitabilities, thereby giving people more choices. Maintain people’s personal independence and dignity.

Hume's philosophy is the first agnostic philosophical system in the history of modern European philosophy. Hume, like I. Kant, played an important role in the development of philosophy. Hume's skepticism provided the theory for British non-religious philosophical thought in the 19th century. Hume's agnostic views were inherited by positivists, Machists and neo-positivists, and had a wide impact on modern Western bourgeois philosophy.

Baidu Encyclopedia-Hume’s Axioms