There is a theory that advises you not to respond to a newborn baby’s cries during the night because it will teach him to comfort himself back to sleep and therefore, he won’t bother you as much. I have to say, this is the worst advice I have ever come across.
A newborn baby in the early stage of growth is very vulnerable and it is the parents’ duty to satisfy every need of their offspring. Letting him ‘cry it out’ could be very psychologically and physically damaging to the child in the early stages of development.
However, later on in the baby’s development (from around six months onwards) the baby will need to learn to comfort himself on his own, however, as far as the right and safest way to look after your newborn is concerned: give him everything he needs, and yes that obviously means some sleepless nights in the beginning.
One your baby has reached the six month mark you may want to consider some basic sleep training methods.