What is Areopagitica?

The Areopagitica is a written speech by John Milton for the liberty of Unlicenced printing to the members of Parliament in 1644. He derived the title from the written oration of the Greek writer,  Isocrates (436-338 B.C). Because of the weakness in his nerves Isocrates could not speak in public but he ventilated his opinion on national issues in written speeches to be read by the people. His seventh oration entitled ''The Areopagitica Discourse or Areopagiticus ' was addressed to the Senate of Athens for the change of the form of democracy. When Milton felt the need to request parliament to withdraw the law of censorship, he chose the title from Isocrates and called his speech Areopagitica.

Is there any similarity between Areopagitica and Areopagiticus ? 

Between these two written speeches, there is a little similarity. Both of these two scholars - Isocrates and Milton,  addressed the legislature of their countries with a request. When the policies of Philip of Macedon threatened the existence of Athens, Isocrates warned the Athenian Parliament to change the form of democracy which prevailed in Athens at that time. He wanted that the power of the court Areopagus should be restored and the liberties of the people should be curtailed. So that Athens could be stronger to face the threat to its existence. But Milton wrote the address to reconsider one of the laws passed by Parliament itself. He made a fervent  appeal to parliament to withdraw the rule by which restriction was imposed upon the freedom of writing.

There are just a few things between the Areopagiticus of Isocrates and the Areopagitica of Milton. They are both addresses written by private persons to the highest legislatives bodies of their respective countries. Both of then appealed to the assemblies to change their policies. But the subject of their appeal was quite different. While Isocrates wanted the control of democracy, Milton's urge was to allow freedom of thinking and writing to each individual.