There’s a lot of research out there about the general flexibility of the brain to adapt to whatever stimulus you pump into it. For example taxi cab drivers have larger areas in their hippocampus dedicated to place cells relative to the general population [1]. There’s also all kinds of work studying general flexibility of the brain in response to novel stimulus like the visual cortex of blind people being dedicated to auditory processing [2 is a broad review]. I guess you could argue that the ability to be flexible is intelligence but the timescales over which a brain functionally changes is longer than a general day to day flexibility. Maybe some brains come into an initial state that’s more predisposed to the set of properties that we deem as “intelligence” but development is so stimulus dependent that I think this definition of a fixed intelligence is functionally meaningless. There are definitely differences in what you can learn as you age but anyone stating we have any causal measure of innate intelligence is claiming far more than we actually have evidence for. We have far more evidence to suggest that we can train at least the appearance and usage of “intelligence”. After all no one is born capable of formal logical reasoning and it must be taught [3,4 kind of weak citations foe this claim but there’s a lot to suggest this that I don’t feel like digging up]

[1] https://pubmed.ncbi.nlm.nih.gov/17024677/ [2] https://www.annualreviews.org/content/journals/10.1146/annur... [3] https://psychologyfor.com/wason-selection-task-what-it-is-an... [4] https://www.tandfonline.com/doi/full/10.1080/14794802.2021.1...

Would you also say that you cannot "train" intelligence?

I would agree that generally, purely acquiring knowledge does not increase intelligence. But I would also argue that intelligence (ie your raw "processing power") can be trained, a bit like a muscle. And acquiring and processing new knowledge is one of the main ways we train that "muscle".

There's lots of examples where your definition of intelligence (intelligence == raw processing power) either doesn't make sense, or is so narrow that it becomes a meaningless concept. Let's consider feral children (ie humans growing up among animals with no human contact). Apparently they are unable or have trouble learning a human language. There's a theory that there's a critical period after which we are unable to learn certain things. Wouldn't the "ability to learn a language" be considered intelligence? Would you therefore consider a young child more intelligent than any adult?

And to answer your question, whether learning about atoms makes you more intelligent: Yes, probably. It will create some kind of connections in your brain that didn't exist before. It's a piece of knowledge that can be drawn upon for all of your thinking and it's a piece of knowledge that most humans would not figure out on their own. By basically any sensible definition of intelligence, yes it does improve your intelligence.

Yes, intelligence can be influenced by training(and other things).

The claim that books know things seems suspicious to me. I consider the act of knowing to be embodied, it is something a person has learned to do and has control over.

Is that how you approach PDF files? Do you feel it in your bones that these flows of bytes are knowing?