> Looking back historically, people like Einstein and Bohr and John Wheeler all took philosophy very seriously; it directly influenced their physics.
I only recently learned that Einstein had three large portraits in his Berlin office: Michael Faraday, James Clerk Maxwell, and Arthur Schopenhauer. Einstein considered Schopenhauer a genius. Friends and colleagues frequently found him reading random passages of "The World as Will and Representation". He even seems to have copied Schopenhauer's hairstyle in later years. Schopenhauer was also very important to Wolfgang Pauli and Erwin Schrödinger [0].
Schopenhauer has few things that could inspire, not necessary his philosophy. He was like the only philosopher contemporary of Hegel who didn't even care what Hegel had to say. While Hegel was wildly popular and created a lot of following, Schopenhauer was just a bitter eccentric dude sitting in his castle... but he wasn't stupid / unable to appreciate Hegel's ideas. He really had a good point.
In a sense, he was kind of like that poor doctor who was ridiculed by his peers for suggesting doctors need to wash their hands (and who later committed suicide because of all the bullying). Sorry, cannot recall his name at the moment.
So, it could've been admiration of determination and confidence in one's own beliefs. More so than the admiration of the beliefs themselves.
The problem was that water and soap wasn't enough. Semmelweis wanted them to wash their hands in a really nasty concoction that was bad for the skin. Lister later came up with a different nasty thing for hand washing and sterilization of equipment.
Another issue is that Semmelweis' data wasn't anywhere near as clean as later hagiographies make them out to be. They were in fact very noisy -- not because he did anything wrong but because of an epidemic that came and went.
One of my favorite Schopenhauer anecdotes is that he had trained his dog to do his shopping. He attached a small basket around the dogs neck, put in money and a shopping list, and the dog would walk to the nearest grocer.
I only recently learned that Einstein had three large portraits in his Berlin office: Michael Faraday, James Clerk Maxwell, and Arthur Schopenhauer. Einstein considered Schopenhauer a genius. Friends and colleagues frequently found him reading random passages of "The World as Will and Representation". He even seems to have copied Schopenhauer's hairstyle in later years. Schopenhauer was also very important to Wolfgang Pauli and Erwin Schrödinger [0].
[0] https://en.wikipedia.org/wiki/Arthur_Schopenhauer#Influence_...