"The progress of science in furnishing the government with means of espionage is not likely to stop with wire tapping. Ways may some day be developed by which the government, without removing papers from secret drawers, can reproduce them in court, and by which it will be enabled to expose to a jury the most intimate occurrences of the home. Advances in the psychic and related sciences may bring means of exploring unexpressed beliefs, thoughts and emotions. 'That places the liberty of every man in the hands of every petty officer' was said by James Otis of much lesser intrusions than these. 1 To Lord Camden a far slighter intrusion seemed 'subversive of all the comforts of society.' Can it be that the Constitution affords no protection against such invasions of individual security?"

“did not believe with the evangelist that . . . truth could be found by abiding in the Word or in becoming the disciple of any leader. Neither did he think it came from intuition or from speculation in metaphysics. He thought it could and would come only from the relentless, disinterested and critical study of facts.”

“Strong, responsible unions are essential to industrial fair play. Without them the labor bargain is wholly one-sided. The parties to the labor contract must be nearly equal in strength if justice is to be worked out, and this means that the workers must be organized and that their organizations must be recognized by employers as a condition precedent to industrial peace.”

“Ashwander v. Tennessee Valley Authority”

“Fear of serious injury cannot alone justify suppression of free speech and assembly. Men feared witches and burnt women. It is the function of speech to free men from the bondage of irrational fears.”

“At the foundation of our civil liberty lies the principle which denies to government officials an exceptional position before the law and which subjects them to the same rules of conduct that are commands to the citizen.”

“Stare decisis is usually the wise policy, because in most matters it is more important that the applicable rule of law be settled than that it be settled right... This is commonly true even where the error is a matter of serious concern, provided correction can be had by legislation. But in cases involving the Federal Constitution, where correction through legislative action is practically impossible, this court has often overruled its earlier decisions. The court bows to the lessons of experience and the force of better reasoning, recognizing that the process of trial and error, so fruitful in the physical sciences, is appropriate also in the judicial function.”