1. Using a food processor, grind the nori seaweed until it's pulverized.
2. Gradually add the chickpeas to the processor and blend well.
3. Pour the preparation into a bowl.
4. Cut the onion, tomato, and celery into small squares.
5. Add the vegetables to the bowl and mix them with the chickpeas.
6. Add the lemon juice and mayonnaise.
7. Mix all ingredients well.