5 plus 5 is 5 plus 5

Yesterday, Sven asked for some Jelly Bean candy from the bulk section of favorite local co-op. I asked him how many he wanted and he said "five." So, I asked him if he knew what 5 plus 5 was, and he didn't understand the question.

When we got him I tried with fewer Jelly Beans. We started with 2 plus 2, and after some explanation, he finally gave me the right answer consistently. So, we graduated to 3 plus 3. That took much less time. But we were out of Jelly Beans because I let him eat the sum of each Arithmetic question.

Later that evening we did 1 plus 1 and he said 2, but he was a little unsure about 1 plus 2 - he finally said 3. Then Sven said "5 plus 5 is 5 plus 5", and ended the conversation at that. He refused to discuss it further.