"Everything pertaining to the study of vocal technic and the art of
singing may be summed up in the one word--Causation. A cause underlies
every effect. If you do not secure the quality of tone you desire, there
must be a reason for it. You evidently do not understand the cause which
will produce the effect. That is the reason why singers possessing
really beautiful voices produce uneven effects and variable results.
They may sing a phrase quite perfectly at one moment. A short time after
they may repeat the same phrase in quite a different way and not at all
perfectly. One night they will sing very beautifully; the next night you
might hardly recognize the voice, so changed would be its quality. This
would not be the case if they understood causation. A student, rightly
taught, should know the cause for everything he does, how he does thus
and so and why he does it. A singer should be able to produce the voice
correctly, no matter in what position the rôle he may be singing may
require the head or body to be in. In opera the head or body may be
placed in difficult unnatural positions, but these should not interfere
with good tone production.