Apart from the trivial constant functions then, singularities are a fact of life, and we must learn to live with them.
–—Arfken, Weber, and Harris, Mathematical Methods for Physicists 7th ed, page 490
The shell has no recycle bin or trashcan. After you remove a file, it's gone forever.
–—Richard Blum, Christine Bresnahan, Linux Command Line and Shell Scripting Bible 3rd ed, page 114