For the rest of us, Topshop presents a knotty dilemma: the rewards can be great (a leather biker jacket I bought seven years ago is still regularly mistaken for Balenciaga) but the sacrifices are akin to a root canal (confusing layouts, too much clothing and herds of teenagers roaming with hyena-like intensity).

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It was the Poincare conjecture, a knotty problem involving circles and spheres, which had dogged mathematicians for a century.

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Personal animus aside, the suit raises a knotty question of responsibility.

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The omnipresent knotty wood paneling gleams with a golden patina, and the lobby is lit with twig-shaped sconces and three enormous antler chandeliers.

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Senhor Vinho restaurant hosts first-class performances amidst ceramic tiled walls and knotty beamed ceilings, accompanied by a seafood-heavy menu.

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At a time when the U.S. is confronting some of the worst, most knotty foreign policy challenges ever, with destabilizing revolts in Syria and across the Arab world, and a situation in Afghanistan that seems to grow worse by the day, it is a huge setback for the CIA suddenly to have to replace its director.

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But he did admit there were some "knotty problems" for anyone not connected to the web and so unable to get a full list of the products contaminated with Sudan 1.

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Knotty problems of the same sort arise whenever you add an ethical overlay to what is normally a purely economic decision, like shopping for coffee, paying an electric bill or buying an index fund.

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That's a lot of plot for one play, especially when it contains 18 characters whose personal relationships are so knotty that they're outlined in the cast list.

WSJ: Fine 'Dining' at Its Best | The Dining Room | Westport Country Playhouse | Nikolai and the Others | Lincoln Center Theater | By Terry Teachout