Every insect pest likes Aubergines
Oh dear Aubergines! Every insect pest likes Aubergines. I suspect this is caterpillars. Are you seeing any droppings anywhere on the plants which is often a sign of caterpillar activity?
If they are young plants sometimes slugs and snails will also eat young leaves. Also mice can attack plants and eat leaves, although I have not seen this on Aubergines. I would suggest you shake the plants and see if anything drops out i.e caterpillars.
If they do, you can either apply Caterpillar Killer nematodes or spray a pyrethrum based spray on them like Insect Killer spray which is safe on edible plants.