It means a song can be written such that none of the lyrics, if taken by their literal meanings, betray what the song is about. The entire meaning and content o

It means a song can be written such that none of the lyrics, if taken by their literal meanings, betray what the song is about. The entire meaning and content of the song is never stated, it requires one to identify words and phrases used in opposition to their normal usage, and realize an alternative meaning that typically connects opposing ideas in colorful ways. Such as "his intelligence was slothish, capable of amazing feats of inactivity..."