“ A man can no more penetrate or understand those mysteries than he can know what the ladies talk about when they go upstairs after dinner. It is only by inquiry and perseverance that one sometimes gets hints of those secrets ”
 William Makepeace Thackeray, Vanity Fair (1847). copy citation

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“but it must be confessed that the ladies held aloof from her, and that their doors were shut to our little adventurer. With regard to the world of female fashion and its customs, the present writer of course can only speak at second hand. A man can no more penetrate or understand those mysteries than he can know what the ladies talk about when they go upstairs after dinner. It is only by inquiry and perseverance that one sometimes gets hints of those secrets; and by a similar diligence every person who treads the Pall Mall pavement and frequents the clubs of this metropolis knows, either through his own experience or through some acquaintance with whom he plays at billiards or shares the joint, something about the genteel world of London, and how, as there are men” source