La matoría de la gente vive al día, y, aunque tenga algún plan a largo plazo, no es más que una pequeña anticipación de algún proceso natural: espera… - B. F. Skinner

One may take the line that metaphorical devices are inevitable in the early stages of any science and that although we may look with amusement today upon the “essences,” “forces,” “phlogistons,” and “ethers,” of the science of yesterday, these nevertheless were essential to the historical process. It would be difficult to prove or disprove this. However, if we have learned anything about the nature of scientific thinking, if mathematical and logical researches have improved our capacity to represent and analyze empirical data, it is possible that we can avoid some of the mistakes of adolescence. Whether Freud could have done so is past demonstrating, but whether we need similar constructs in the future prosecution of a science of behavior is a question worth considering.

Education is what survives when what has been learnt has been forgotten.

Man's power appears to have increased out of all proportion to his wisdom. He has never been in a better position to build a healthy, happy, and productive world; yet things have perhaps never seemed so black.