“ In marriage what is looked to is not intellectual entertainment, but the production of children: it is a bond of the heart, [pg 355] not of the head. ”
 Arthur Schopenhauer, The World as Will and Representation (1819). copy citation

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“Also marriages from love are sometimes consummated between natures which are mentally very different: for example, the man is rough, powerful, and stupid; the woman tenderly sensitive, delicately thoughtful, cultured, æsthetic, &c.; or the man is a genius and learned, the woman a goose:
“ Sic visum Veneri; cui placet impares Formas atque animos sub juga aënea Sævo mittere cum joco. ” In marriage what is looked to is not intellectual entertainment, but the production of children: it is a bond of the heart, [pg 355] not of the head. It is a vain and absurd pretence when women assert that they have fallen in love with the mind of a man, or else it is the over-straining of a degenerate nature. Men, on the other hand, are not determined in their instinctive love by the qualities of character of the woman; hence so many Socrateses have found their Xantippes; for example, Shakspeare, Albrecht Dürer, Byron, &c.” source