He also had the gift of dyslexia. Leonardo constantly sketched his ideas for inventions, and most of the time wrote his notes backwards. Writing from right-to-left in mirror image. This unusual trait is shared by many left-handed dyslexic people.
Professional services described as Davis™, Davis Dyslexia Correction®, Davis Symbol Mastery™, Davis Orientation Counselling™, Davis Math Mastery™, Davis Attention Mastery™, Dyslexia the Gift® and Gift of Dyslexia® may only be provided by persons who are employed by a licensed Davis Specialist, or who are trained and licensed as Davis Facilitators by Davis Dyslexia Association International.