"Thoughtless people are not unusual," observed the Scarecrow, "but I consider them more fortunate than those who have useless or wicked thoughts and … - L. Frank Baum

"Thoughtless people are not unusual," observed the Scarecrow, "but I consider them more fortunate than those who have useless or wicked thoughts and do not try to curb them. Your oil can, friend Woodman, is filled with oil, but you only apply the oil to your joints, drop by drop, as you need it, and do not keep spilling it where it will do no good. Thoughts should be restrained in the same way as your oil, and only applied when necessary, and for a good purpose. If used carefully, thoughts are good things to have."