Robert Wilson&#x27;s knife quote did not describe Lincoln in the White House, but in the 1830s, when Lincoln was in his 20s and trying to deal with debt, career uncertainties, courting, deaths, and malaria.  It was a hard hard decade for him.<p>One clarification.  Mr. Shenk is interested in idiopathic depression.  It is interesting that malaria was well-known among frontier dwellers to cause terrible depression of spirits afterwards -- i.e. a secondary depression caused by malaria itself.  Lincoln was indeed low during his malarious period, but this has no bearing on the question of whether he had idiopathic depression, except that peri-malaria depression cannot be used as evidence for idiopathic depression.