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There are certainly a number of different possible explanations given by the awestruck and curious congregation to the reason behind Mr. Hooper's new fashion accessory. Goodman Gray, for example, says that Mr. Hooper has gone mad - the only possible explanation from his point of view for such a behaviour. Some think that he has worn his eyes out by reading at night that he needs to shade them. The physician of the village thinks that "something must surely be amiss with Mr. Hooper's intellects," and his fiancée intimates that the congregation suspect some kind of secret sin. This last idea is the one that comes to be generally accepted, and is indeed referred to by Reverend Mr. Clark at the end of Mr. Hooper's life.
Various possibilities are discussed but it seems therefore as if the one that becomes commonly accepted is that Mr. Hooper has donned this black veil as a symbol of some secret sin.