The constant flux and caprice of mental events do not admit of the establishment of stable experimental conditions. - Hermann Ebbinghaus

The relation of repetitions for learning and for repeating English stanzas needs no amplification. These were learned by heart on the first day with less than half of the repetitions necessary for the shortest of the syllable series.

The musician writes for the orchestra what his inner voice sings to him; the painter rarely relies without disadvantage solely upon the images which his inner eye presents to him; nature gives him his forms, study' governs his combinations of them

The schoolboy doesn't force himself to learn his vocabularies and rules altogether at night, but knows that he must impress them again in the morning.