Intertextuality is an extremely interesting aspect of writing in literary texts. It refers to the relationship between any two texts. This ‘relationship’ could occur when one text is inspired from another. The latter one could be either imitating a certain aspect of the preceding text, parodying its content, reiterating some part of the content or simply taking up phrases, vocabulary or diction particular to some other text.
This relationship could be considered while aiming to understand a text better. It’s indirectly implied meaning could be gauged by keeping in mind the wider meanings it’s signalling to. Such aspects tend to add to the level of interest that the readers take in a particular work. Intertextual inferences can also allow the readers to view the text in a particular light, which could work in the favour of the author.
For instance, Tom Stoppard recreated Shakespeare’s Hamlet into a revised story called Rosencrantz and Guildenstern are Dead. This time, the story was narrated by two very uncommon characters. This would give a larger context for the audience to understand the story, as they would have even that information that has not been necessarily portrayed in the new play (through the knowledge of the old play).
It would be interesting to note that even Shakespeare himself applied intertextuality to the play named Hamlet as he based the main storyline on a very famous and revered legendary tale called Amleth. So, that’s even deeper intertextuality.
Other examples could include references to some more texts:
I knew he was lying as his nose began to grow long (reference to Pinocchio)
I don’t think we can escape so much traffic in just twenty minutes, I wish I had Aladdin’s carpet with me right now! (Aladdin)
There are different types of intertextuality:
Allusion: Reference toward some concept without directly mentioning it (e.g. She was so happy as if she had won a golden ticket - reference to Charlie and the Chocolate Factory)
Calque: When words are borrowed from a foreign language, e.g. saying vice versa to mean the other way around.
Plagiarism: Stealing someone else’s content without their permission; this has quite a negative connotation.
Translation: Putting one work into another language (having done with permission and respect to copyright could set this apart from plagiarism.
Quotation: Taking some particular line from other work for reference.
There can be certain weaknesses of this concept as well; for instance, in order to be able to comprehend the reference being drawn, one must possess the prior knowledge of the other text. Otherwise, it would not make sense.
Intertextuality is an interesting device; best of luck implementing it in your own writing as well!