Napoleon, despite the persona he has, is far from a complex man at times. He ate mainly bread and meat with some rice, he particularly fond of a roast chicken; his fashion sense was usually straight forward, he only ever wore a uniform of a Colonel of the Chasseurs a Cheval while his subordinates would spend thousands to hundreds of thousands on their uniforms. However, he was certainly a worldly man of the mind. He loved music and was a particularly skilled mathematician that was a member of the French Academy of Sciences, an honor that he held highly until he became Emperor (and that one is sort of bigger than the French Academy of Sciences).

Which is why he supposedly said this, from Napoleon: A Life By Andrew Roberts, "Napoleon didn't personally admire the metric system that Laplace invented, saying, 'I can understand the twelfth part of an inch, but not the thousandth part of a metre,' but he nonetheless forced it through after 1801 in the interests of commercial consistency."

I'm highly suspect of this quote as he was a gifted and well known mathematician as well as being one of the top of his class, both of which would require him to understand abstract of calculus and be able to mentally visualize the necessary mathematics to sight artillery. The idea of him being unable to understand a fraction of something is odd to me as someone who's studied.