"Why hide ~/Library but not /Library, the similar folder located at the root level of your drive, which holds systemwide support files? Most likely because only admin users can modify/Library, and Apple assumes that a user with admin-level privileges will know what he or she is doing. Yes, I realize that’s a questionable assumption, given that the first user account on a Mac is always set up as an admin account."
These words can be found in an article in Macworld
http://www.macworld.com/article/161156/2011/07/view_library_folder_in_lion..html
The article is called: "18 ways to view the ~/Library folder in Lion"
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