Professor Ebbinghaus by doing experiment with students, how faster they memorize. He gave them a long list of non~ sense syllables to memorize, such as “deyux,” “qoli,” and so on. So result was 38 repetition.
That is a very significant discovery about the working of our memories. It means that we know now that the man who sits down and repeats a thing over and over until he finally fastens it in his memory, is using twice as much time and energy as is necessary to achieve the same results when the repeating process is done at judicious intervals. This peculiarity of the mind-if we can call it suchcan be explained by two factors: First, during the intervals between repetitions, our subconscious minds are busy making the associations more secure. As Professor James sagely remarks: “We learn to swim during the winter and to skate during the summer.” Second, the mind, coming to the task at intervals, is not fatigued by the strain of an unbroken application. Sir Richard Burton, the translator of the “Arabian Nights,” spoke twenty-seven languages like a native: yet he confessed that he never studied or practiced any language for more than fifteen minutes at a time, “for, after that, the brain lost its freshness.”
Here is a very helpful discovery about the way in which we forget. Psychological experiments have repeatedly shown that of the new material we have learned, we forget more during the first eight hours than during the next thirty days. An amazing ratio! So, immediately before you go into a business conference or a PTA meeting or a club group, immediately before you make a speech, look over your data, think over your facts, refresh your memory.