Right here we ask whether this first meaning of freedom does not have an important bearing on the question of ethical obligation. Is it, indeed, not plain that just as we cannot do what is physically impossible, so there is no valid obligation under these conditions? This, however, is something which the intuitionists and the idealists have persistently ignored, regarding it often as somehow the very acme of virtue to declare as an ideal of conduct something which is totally impossible of realization, and thereby fostering the neurotic temperament instead of ethical enlightenment. Yet it is plain that if, while being unable to do the impossible, I still am pathologically anxious about it, I shall succeed only in accumulating impatience and turmoil, and be forced to get what sour consolation I can from Schopenhauer, or else to “gnaw the file” in some other fashion. Moreover, according to a mechanistic ethics, I am an evil person as long as I waste energy in this fashion, or in demanding consolation for my erroneous sentiment. Not only am I bound to fail, and thereby to create discord rather than relieve it, but I am also losing time and energy which might have gone into more profitable pursuits. On the other hand, while we do not yet say that we are under obligation to perform every physically possible action, yet every valid urgency still lies in that direction. The second meaning of the word “freedom” is _absence of external restraints_ imposed by physical obstacles or generated by human beings. No man is free to act when external hindrances are too great for him to overcome. Thus while it is possible for a sound man to walk either forward or backward, he cannot keep on walking in a straight line if his path is intercepted by the sheer wall of a hundred-foot cliff, or if some one stronger than himself obstructs his going. Excellent examples of such thwarting occur in the Greek mythology of Hades. Tantalus was forever hindered by the gusts of wind from plucking the fruit from the tree; Sisyphus could not force the stone over the brow of the hill; and the daughters of Danaus lost all the water they carried in their sieves. They were not, therefore, _free_ to perform these actions. They may, it is true, have everlastingly _wished_ them, but they could not _will_ them.