Because a good Julian quote is like Christmas. He and I were discussing whether we had run out of an item and, while he said we were all out, I on the other hand felt certain we had more. I did some digging and sure enough, there were a few more, and we rejoiced. Julian, acknowledging he was incorrect, remarked,
And I thought I was so stupid! But I amn't!
And thus a new catch phrase was born. I don't actually know what it means, since he was the one who thought we were out. But oh well, so funny. Amn't. :D Why not, right?