"But—It was a drug that caused that change in the story, wasn't it?"
"Well? Do you suspect your friend of being addicted to some mysterious drug? Is that the latest hypothesis?"
"Is there such a drug? One that could change a person's character?"
"All alkaloids do that, Honey. Some of them stimulate, some depress, some breed frenzies, and some give visions of delight—but all of them influence one's mental and emotional organization, which you call character. So for that matter, does a square meal, or a cup of coffee, or even a rainy day."
"But isn't there a drug that can separate good qualities from evil, like the story?"
"Emphatically not, Pat! That's not the trouble with this pesky boy friend of yours."
"Well," said the girl doubtfully, "I only wish I had as much faith in your psychologies as you have. If you brain-doctors know it all, why do you switch theories every year?"
"We don't know it all. On the other hand, there are a few things to be said in our favor."
"What are they?"
"For one," replied the Doctor, "we do cure people occasionally. You'll admit that."