Earlier this week, I heard something on the radio that I found interesting: it was about how young people nowadays believe you can learn more about how a person really is from the books they own than from their social media profile. What do you think of that?
I´m not well-versed in social media, so on that side, I prefer not to give an opinion, beyond repeating the usual argument that says that social media only shows us a minuscule portion of a person´s life, often carefully selected, and never telling the whole story, not even remotely.
On the topic of books, I can comment a bit more. As I´ve probably told you already, I grew up in a family with many, many books at home, and throughout my life, I´ve spent countless hours reading; it´s a habit I´ve been progressively losing, unfortunately, and that I want to resume... But anyway, we could say I also inherited that soft spot for reading, and I´ve done my best to pass it on to my daughters as well.

(Sign seen in a well-known department store in Madrid, El Corte Inglés: "Each book is a window to the world. Come and have a look.")
This summer, I spent time decluttering some of my father´s books, and it is true that they reflected many of his interests: politics, history, art... But I think the key is not that they were his books, precisely, but simply that they were his things, the things he chose to have in his home, because he liked them and used them regularly. For my father, reading was a really important part of daily life; for others, it will be other things.
So maybe I would slightly rephrase that comment to say that you can learn more about how a person really is by visiting their home, or their room: the place they consider theirs and that they make their own, inadvertently making it reflect their character and preferences. In our house, there are many books, yes, but there are also games and many other things that reflect the way we are and what is important to us.
They say a book is a window to the world; perhaps the window to a person is not their social media, but the place where they live and are allowed to be themselves.