english: 19th century psychologist  Herman Ebbinghaus demonstrated that we normally forget 40% of new material within the first twenty minutes, a phenomenon known as the forgetting curve.
non_english: Psiholog Herman Ebbinghaus je v 19. stoletju pokazal, da ponavadi v prvih dvajsetih minutah pozabimo 40 odstotkov novega materiala, čemur pravimo krivulja pozabljanja.