We frequently hear repeated the assertion, "Everybody is a little insane," and the quotation is reported as coming from an expert in insanity. This quotation is untrue. The fact is that anyone is liable to mental disorder; but mental disorder is not insanity. To illustrate: a green glove is shown to a certain man and he asserts that its color is brown, and you cannot prove to him that he is wrong, because he is color-blind. Green and brown appear alike to him. This is mental disorder, but not insanity. Again, a friend will explain to you how he can make a large profit by investing his money in a certain way. He does so invest it and loses it, because he has overlooked certain factors, has not given proper weight to certain influences, and has ignored probable occurrences, all of which were apparent to you. He was a victim of his mental disorder, his judgment, reason, and conception being faulty; yet he was not insane. Again, you answer a letter from a correspondent, copying on the envelope the address you read at the head of his letter. A few days later your answer is returned to you undelivered. In astonishment, you refer to his letter and find that you have misread the address he gave, mistaking the number of his house. This was an instance of mental disorder in your not reading the figure aright; but it was not insanity. _What Autopsies of the Brain Reveal_ The changes in the brain accompanying or resulting from disease, as found in some chronic cases of insanity in which autopsies are made, consist largely in alteration of the nerve cells of the brain. The cells are smaller and fewer than they should be, they are altered in shape, and their threads of communication with other cells are broken. Nerve cells and often large areas of gray matter are replaced by connective tissue (resembling scar tissue), which grows and increases in what would otherwise be vacant spaces. All areas which contain this connective tissue, this filling which has no function, of course, cease to join with other parts of the brain in concerted action, and so the power of the brain is diminished, and certain of its activities are restricted or abolished. _Curious Illusions of the Insane_