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Encyclical letter of Pope leo xiii on human liberty, issued June 20, 1888. In what is in effect a miniature philosophical treatise on the nature of human liberty, Leo examined the so-called "modern liberties" and issued certain practical directives to European, especially French, Catholics.

The 19th century had seen the rise of the political and ethical philosophy that came to be called liberalism. Often referred to as continental or European liberalism (to distinguish it from more recent American usage), this philosophy embodied the denial of any divine authority and the refusal to accept it as a law or norm of the human will. Thus, in Leo's words, "What naturalists or rationalists aim at in philosophy, that the supporters of liberalism are attempting in the domain of morality and politics. The fundamental doctrine of rationalism is the supremacy of the human reason, which proclaims its own independence and constitutes itself the supreme principle and source and judge of truth. Hence, these followers of liberalism deny the existence of any divine authority to which obedience is due, and proclaim that every man is the law to himself; from which arises that ethical system which they style independent morality, and which under the guise of liberty, exonerates man from any obedience to the law of God and substitutes a boundless license" (par. 15).

Opposing this doctrine, Leo explains human liberty as it has ever been "cherished by the Catholic Church." He distinguishes between natural liberty, which belongs to man as endowed with intelligence, and moral liberty, which consists in choosing that good only which is in conformity with the judgment of reason. He is primarily concerned with moral liberty. Because the intellect and will of man are defective, law is morally necessary as a guide to knowledge of what is objectively reasonable and unreasonable. But law must be understood adequately. Hence, natural law and human (civil) law are analyzed. Their source is in divine law, which is ultimately "the sole standard and rule of human liberty" (par. 10). True moral liberty, therefore, requires submission to the authority of God commanding good and forbidding evil.

As he had already done on other occasions, Leo discusses the four major "modern liberties": liberty of worship, of speech and press, of teaching error, and of conscience. His purpose is to distinguish between the good and evil elements in these liberties. The Church approves the good, and condemns the evil.

The last part of the encyclical comments indirectly on the situation in France, where a dispute existed between conservative and progressive Catholics. The dispute was as political as it was doctrinal, and the pope encouraged men on both sides of it to strike a balance, pointing out that the Church accepts any form of government that truly promotes the common good, and that Catholics should take part in public affairs.

Bibliography: Acta Sanctae Sedis 20:593613, has the official Latin text.

[d. l. lowery]

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