According to Swami Bharati, this definition does not include any
reference to the purpose or purposes of mantra, for the statement
of purpose is a material statement, which must be excluded from
a definition, which is a set of formal propositions of exceptionless
validity.
If there is a single exception to a statement, then that
statement forfeits its claim to being a definition. As there is a
conceivable exception with regard to the purpose of mantra,
purpose
could not be included.