<P> This idea was later developed in ancient philosophy by the Stoic school . Stoic epistemology generally emphasized that the mind starts blank, but acquires knowledge as the outside world is impressed upon it . The doxographer Aetius summarizes this view as "When a man is born, the Stoics say, he has the commanding part of his soul like a sheet of paper ready for writing upon ." </P> <P> During the Middle Ages Aristotle's theory of tabula rasa was developed by Islamic philosophers starting with Al Farabi, developing into an elaborate theory by Avicenna and demonstrated as a thought experiment by Ibn Tufail . For Avicenna (Ibn Sina), for example, the tabula rasa is a pure potentiality that is actualized through education, and knowledge is attained through "empirical familiarity with objects in this world from which one abstracts universal concepts" developed through a "syllogistic method of reasoning in which observations lead to propositional statements which when compounded lead to further abstract concepts". The intellect itself develops from a material intellect (al -' aql al - hayulani), which is a potentiality "that can acquire knowledge to the active intellect (al -' aql al - fa'il), the state of the human intellect in conjunction with the perfect source of knowledge". So the immaterial "active intellect", separate from any individual person, is still essential for understanding to occur . </P> <P> In the 12th century CE the Andalusian Muslim philosopher and novelist Abu Bakr Ibn Tufail (known as "Abubacer" or "Ebn Tophail" in the West) included the theory of tabula rasa as a thought experiment in his Arabic philosophical novel, Hayy ibn Yaqdhan in which he depicted the development of the mind of a feral child "from a tabula rasa to that of an adult, in complete isolation from society" on a desert island, through experience alone . The Latin translation of his philosophical novel, entitled Philosophus Autodidactus, published by Edward Pococke the Younger in 1671, had an influence on John Locke's formulation of tabula rasa in An Essay Concerning Human Understanding . </P> <P> A similar Islamic theological novel, Theologus Autodidactus, was written by the Arab theologian and physician Ibn al - Nafis in the 13th century . It also dealt with the theme of empiricism through the story of a feral child on a desert island, but departed from its predecessor by depicting the development of the protagonist's mind through contact with society rather than in isolation from society . </P>

Rationalists reject the idea that the human mind as a blank slate