Non-Logical Inspiration

Hello!
I wanted to study a stray chestnut which says i require 1700 inspiration which i have (to get my pottery done), but the game gives me a error message i need double of that!
Why?

I wanted to study a stray chestnut which says i require 1700 inspiration which i have (to get my pottery done), but the game gives me a error message i need double of that!
Why?
