Here is one of Kierkegaard’s most arresting images: a man sews a garment, he works with care and persistence but he refuses to knot the thread he sews with and so it pulls through the cloth as he proceeds; the man sees this but keeps on sewing, firm in his commitment to the task. Kierkegaard used this image in various books including The Sickness unto Death, because it illustrates the futility of speculative philosophy: the philosophers have worked long and hard—they’ve worked for centuries, in fact—but they have achieved less than they imagine that is credible or lasting because they…