Psychologists are dusting off 19th-century explanations of déjà vu. Have we been here before? In the summer of 1856, Nathaniel Hawthorne visited a decaying English manor house known as Stanton Harcourt, not far from Oxford. He was struck by the vast kitchen, which occupied the bottom of a 70-foot tower. "Here, no doubt, they were accustomed to roast oxen whole, with as little fuss and ado as a modern cook would roast a fowl," he wrote in an 1863 travelogue, Our Old Home. Hawthorne wrote that as he stood in that kitchen, he was seized by an uncanny feeling: "I was haunted and perplexed by an idea that somewhere or other I had seen just this strange spectacle before. The height, the blackness, the dismal void, before my eyes, seemed as familiar as the decorous neatness of my grandmother's kitchen." He was certain that he had never actually seen this room or anything like it. And yet for a moment he was caught in what he described as "that odd state of mind wherein we fitfully and teasingly remember some previous scene or incident, of which the one now passing appears to be but the echo and reduplication."When Hawthorne wrote that passage there was no common term for such an experience. But by the end of the 19th century, after discarding "false recognition," "paramnesia," and "promnesia," scholars had settled on a French candidate: "déjà vu," or "already seen."The fleeting melancholy and euphoria associated with déjà vu have attracted the interest of poets, novelists, and occultists of many stripes. St. Augustine, Sir Walter Scott, Dickens, and Tolstoy all wrote detailed accounts of such experiences. (We will politely leave aside a certain woozy song by Crosby, Stills, Nash & Young.)