Reply to self: of course, the prime example is counting. If you have five breads, you can sell three, and have two breads left after that. Similarly, If you ha

Reply to self: of course, the prime example is counting. If you have five breads, you can sell three, and have two breads left after that. Similarly, If you have five apples, you can sell three, and have two apples left after that. You didn’t have to learn separate addition tables for breads, apples, etc. Instead you learned that all such problems essentially are the same, and you learned how to manipulate the equivalence classes of those (which are called 5, 3, and 2)