Are Catholics forbidden to belong to all secret societies, or only to Masonry?

The Catholic Answers

The Catholic Church does not condemn any society merely because it is secret in its own transactions of business. Every society may have its lawful secrets. A family is a society, and no family is obliged to call in strangers and exhibit all its affairs to the public gaze. But the Church does condemn those societies whose form of secrecy can be dangerous to religion, or to the state, or which can lead to the violation of conscience. Many Catholic societies which have their own legitimate secret business are permitted by the Church. But before giving her sanction, she makes sure that such secret business is limited to lawful matters, and that the constitutions of such societies are based upon Christian principles, containing nothing in any way opposed to the law of God.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty