Develop your own opinions and reasonings
Authors/Experts are no different to us. They are human too. Their isn’t much to argue about logical facts. One cannot argue over statements like 1+1=2. But for other things there is always a room for introspection and finding flaws and fixing it.
While coding many try to follow “best practices” without giving them a thought. Many follow Agile “practices” without knowing or reasoning why.
Not having your own reasoning makes you susceptible to ideological thinking along with it’s upsides and down sides.
By not reasoning yourself, you are not being unique, you are just a replicate of someone else’s thinking.