You will see, therefore, why I cannot believe that constitutional expedients alone, however substantial, will prevent the invasion of liberty. They will work just so long as people are determined they shall work, and no longer. They are valuable because, since they have been consecrated by tradition, their invasion tends to awaken, at least in some of us, a prejudice to which we have become habituated. But to keep them active and alive, requires a deliberate and purposive effort it is by no means easy to make when the result of doing so conflicts with some other object keenly desired. That is, I think, capable of a simple demonstration. No class of men is so carefully trained as the judiciary to the habit of a balanced mind. Yet if you examine the observations of judges in cases where their passions are deeply involved you will note how great is the effort they have to make to show tolerance to antagonistic views. Nor do they always succeed. In most of the classic English blasphemy cases, for example, the judge has too often been, either consciously or unconsciously, an additional counsel for the prosecution.[22] In many of the American Espionage Acts cases what chiefly emerges from the summing up of the judge is a desire, at all costs, to see that the prisoner does not secure an acquittal.[23] Recent injunction cases in America show a desire, no doubt unconscious, on the part of the Court, to lend aid and countenance to a social philosophy of which it happens to approve. I conclude, therefore, that in general we shall not allow, as a society, the mechanisms of the state to serve the cause of freedom unless we approve the objects at which freedom aims. In a time of crisis, particularly, when the things we hold most dear are threatened, we shall find the desire to throw overboard the habits of tolerance, almost irresistible. For those habits are not in Nature, which teaches us that opinions we deem evil are fraught with death. They come from our social heritage, and are part of a process the value of which we must relearn continuously if we are to preserve it. That is the meaning of the famous maxim that eternal vigilance is the price of liberty. It is why, also, it becomes necessary in each age to restate the case for freedom, if it is to be maintained. V