It is the capability of thinking and understanding Dhamma that matters in realizing Nibbana not the educational qualifications. Either with a good educational background or not, one can realize Nibbana if that person can compare Dhamma to oneself according to the way Buddha showed it. However, it is important to remember Dhamma after reading it or listening to it since it helps understanding it. Of course, even some people who could not remember Dhamma realized it in the past… There was a venerable monk known as Chullapanthaka. Even after trying for four months, he could not remember at least two sentences of one stanza he tried to remember that stanza by heart. Venerable Thero tried hard, but his attempt was not successful. Venerable Thero’s brother was also a monk, and he lived in the same temple where Venerable Chullapanthaka lived. That Thero thought that Venerable Chullapanthaka cannot continue living as a monk since he could not remember at least two sentences of a stanza. He further thought that it was a good idea for Venerable Chullapanthaka to leave the temple and go back home to start a lay life, so that at least then he will be able to cultivate merits. Thus, he told Venerable Chullapanthaka this idea. Since there was nothing else to do, Venerable Chullapanthaka decided to leave the monk-hood. He was really upset and was crying sitting at the temple gate when the greatly benevolent teacher of us, the Supreme Buddha, saw this incidence with his divine eye. Lord Buddha then came to Venerable Chullapanthaka and gave him a clean piece of white cloth asking Venerable Chullapanthaka to rub the cloth saying “rajo haran”. It means “may the dirt be gone!” As instructed by the Supreme Buddha, he rubbed that white cloth continuously saying “rajo haran, rajo haran, rajo haran….”In a moment that clean white cloth became brownish and dirty. By observing it, Venerable Chullapanthaka started to cogitate about the change wisely. Venerable Thero realized the dirty status of his body. “This much of a clean cloth became dirty after a moment of rubbing it because this body is dirty.” Lord Buddha saw Venerable Chullapanthaka’s mind was concentrated on to a Vidarshana Meditation (a meditation focused on cogitating the true way of life) when he was thinking about the clean cloth. Lord Buddha then came to him in a second with his divinely power (Irdi) and resided a stanza, so that Venerable Chullapanthaka’s mind was driven to Nibbana. When Venerable Chullapanthaka was contemplating according to that stanza his mind became concentrated. He focused on the true nature of this life more and more deeply until he became an Arahant by eradicating all the defilements within him. He freed himself from all the suffering of birth, sickness, aging, and death. It was a person who had an insufficient memory power who realized Dhamma. He could realize Dhamma because Lord Buddha preached him Dhamma which helped to raise his consciousness leading him to Nibbana. Therefore, you can see that this Dhamma can be realized by anyone who could cogitate about it wisely.