Comment by Metatron

It's the easy option to opt for retaliation. I'd advise against if only to keep your own principles strong. If you value openness, talk to them. If they cannot find a replacement during the two week timeframe then they may ask you to stay on longer. Use this as leverage for fairer pay during that period (unless you already have to move into your new job). If they do not offer more, then stick to your principles and leave. That is the fair and just way of handling them without weakening your own moral code. And finally, good luck!