"the mind in its primary state," 1530s, from Latin tabula rasa, literally "scraped tablet," from which writing has been erased, thus "blank and ready to be written on," from tabula (see table (n.)) + rasa, fem. past participle of radere "to scrape away, erase" (see raze (v.)).
A loan-translation of Aristotle's pinakis agraphos, literally "unwritten tablet" ("De anima," 7.22). Compare modern colloquial blank slate, etc. in similar senses.