Alexander of Aphrodisius said that there are three causes which prevent men from discovering the exact truth: first, arrogance and vainglory; secondly, the subtlety, depth, and difficulty of any subject which is being examined; thirdly, ignorance and want of capacity to comprehend what might be comprehended. These causes are enumerated by Alexander.
At the present time there is a fourth cause not mentioned by him, because it did not then prevail, namely, habit and training. We naturally like what we have been accustomed to, and are attracted towards it. This may be observed amongst villagers; though they rarely enjoy the benefit of a douche or bath, and have few enjoyments, and pass a life of privation, they dislike town life and do not desire its pleasures, preferring the inferior things to which they are accustomed, to the better things to which they are strangers; it would give them no satisfaction to live in palaces, to be clothed in silk, and to indulge in baths, ointments, and perfumes.
The same is the case with those opinions of man to which he has been accustomed from his youth; he likes them, defends them, and shuns the opposite views. This is likewise one of the causes which prevent men from finding truth, and which make them cling to their habitual opinions.
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