What does it mean by read between the lines?

What else do you think experts can learn from studying the language of written work? what do you think is the value of studying the language of william shakespeare whose writing is over hundreds of years old?

Brutus: but as he was ambitious, i slew him. . who is here so base that would be a bondman? if any, speak, for him have i offended. who is here so rude that would not be a roman? if any, speak, for him have i offended. who is here so vile that will not love his country? if any, speak, for him have i offended. i pause for a reply. which rhetorical device does brutus use in this excerpt?

How did rick respond to this conflict