g) To promote the harmonious development of the whole of Portuguese territory, with particular regard to the ultraperipheral nature of the Azores and Madeira archipelagos; h) To promote equality between men and women. Article 10 (Universal suffrage and political parties) 1. The people exercise political power by means of universal, equal, direct, secret and periodic suffrage, referendum and the other forms provided for in the Constitution. 2. Political parties exist in order to contribute to the organisation and expression of the will of the people, with respect for the principles of national independence, the unity of the state and political democracy. Article 11 (National symbols and official language) 1. The National Flag, which is the symbol of the sovereignty of the Republic and of Portugal’s independence, unity and integrity, is that adopted by the Republic formed by the Revolution of the 5th of October 1910. 2. The national anthem is A Portuguesa. 3. The official language is Portuguese. PART I Fundamental rights and duties TITLE I General principles Article 12 (Principle of universality) 1. Every citizen enjoys the rights and is subject to the duties enshrined in the Constitution. 2. Legal persons enjoy the rights and are subject to the duties that are compatible with their nature. Article 13 (Principle of equality) 1. All citizens possess the same social dignity and are equal before the law. 2. No one may be privileged, favoured, prejudiced, deprived of any right or exempted from any duty for reasons of ancestry, sex, race, language, territory of origin, religion, political or ideological beliefs, education, economic situation, social circumstances or sexual orientation.