Meaning of the word "a book is a good friend when it lays bare the errors of the past" in English

What does "a book is a good friend when it lays bare the errors of the past" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

a book is a good friend when it lays bare the errors of the past

US /ə ˈbʊk ɪz ə ˈɡʊd ˌfrend wen ɪt ˈleɪz ˌber ði ˈer.ər əv ðə ˈpæst/
"a book is a good friend when it lays bare the errors of the past" picture
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