It is impossible to estimate how far Lincoln foresaw the strain to which a firm stand against slavery would subject the Union. It is likely enough that those worst forebodings for the Union, which events proved to be very true, were confined to timid men who made a practice of yielding to threats. Lincoln appreciated better than many of his fellows the sentiment of the South, but it is often hard for men, not in immediate contact with a school of thought which seems to them thoroughly perverse, to appreciate its pervasive power, and Lincoln was inclined to stake much upon the hope that reason will prevail. Moreover, he had a confidence in the strength of the Union which might have been justified if his predecessor in office had been a man of ordinary firmness. But it is not to be supposed that any undue hopefulness, if he felt it, influenced his judgment. He was of a temper which does not seek to forecast what the future has to show, and his melancholy prepared him well for any evil that might come. Two things we can say with certainty of his aim and purpose. On the one hand, as has already been said, whatever view he had taken of the peril to the Union he would never have sought to avoid the peril by what appeared to him a surrender of the principle which gave the Union its worth. On the other hand, he must always have been prepared to uphold the Union at whatever the cost might prove to be. To a man of deep and gentle nature war will always be hateful, but it can never, any more than an individual death, appear the worst of evils. And the claim of the Southern States to separate from a community which to him was venerable and to form a new nation, based on slavery and bound to live in discord with its neighbors, did not appeal to him at all, though in a certain literal sense it was a claim to liberty. His attitude to any possible movement for secession was defined four years at least before secession came, in words such as it was not his habit to use without full sense of their possible effect or without much previous thought. They were quite simple: "We won't break up the Union, and you shan't."