Why TM can't be learned from a book
A TM initiation alters the brainwave pattern of the one performing the puja.
When the teacher then passes on the mantra to the person learning meditation he
also passes on a brainwave state by a process know in neurophysiology as
entrainment. Brainwave entrainment or "brainwave synchronization," is any
practice that aims to cause brainwave frequencies to fall into step with a
periodic stimulus having a frequency corresponding to the intended brain-state.
This is only one of the Neuro effects of a TM initiation which is a very well
crafted design of several which lead to a self transcending effect of the
mantra.