Tabula rasa (Latin: blank slate) is the epistemological thesis that individuals are born without built-in mental content and that their knowledge comes from experience and perception.
In Western philosophy, traces of the idea that came to be called the tabula rasa appear as early as the writings of Aristotle. Aristotle writes of the unscribed tablet in what is probably the first textbook of psychology in the Western canon, his treatise "Περί Ψυχῆς" (De Anima or On the Soul, Book III, chapter 4). However, besides some arguments by the Stoics and Peripatetics, the notion of the mind as a blank slate went much unnoticed for more than 1,000 years.
In the 12th century, the Andalusian-Islamic philosopher and novelist Ibn Tufail (known as "Abubacer" or "Ebn Tophail" in the West) demonstrated the theory of tabula rasa as a thought experiment through his Arabic philosophical novel, Hayy ibn Yaqzan, 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.
The writings of Avicenna, Ibn Tufail and Aquinas on the tabula rasa theory stood unprogressed for several centuries. In fact, our modern idea of the theory is mostly attributed to John Locke's expression of the idea in An Essay Concerning Human Understanding in the 17th century. In Locke's philosophy, tabula rasa was the theory that the (human) mind is at birth a "blank slate" without rules for processing data, and that data is added and rules for processing are formed solely by one's sensory experiences. The notion is central to Lockean empiricism. As understood by Locke, tabula rasa meant that the mind of the individual was born "blank", and it also emphasized the individual's freedom to author his or her own soul. Each individual was free to define the content of his or her character - but his or her basic identity as a member of the human species cannot be so altered. It is from this presumption of a free, self-authored mind combined with an immutable human nature that the Lockean doctrine of "natural" rights derives.
The tabula rasa concept became popular in social sciences in the 20th century. Eugenics (mainstream in the late 19th and early 20th centuries) came to be seen not as a sound policy but as a crime. The idea that genes (or simply "blood") determined character took on racist overtones. By the 1970s, some scientists had come to see gender identity as socially constructed rather than rooted in genetics (see John Money), a concept still current (see Anne Fausto-Sterling), although strongly contested. This swing of the pendulum accompanied suspicion of innate differences in general (see racism) and a propensity to "manage" society, where the real power must be if people are born blank.