While spanking or slapping children used to be very common in families, today it is much more rare. The idea of "Spare the rod, spoil the child" suggested that you could beat good behavior into children and that fear was the best teacher/motivator. In the modern day, we have found such punishment/abuse unnecessary to raise kids. There are more effective methods.
Are we not supposed to be models of behavior for our children? What are the consequences of hitting a child? Is it unreasonable to image that a child will draw the conclusion that when things are not to his satisfaction, he should hit someone? It doesn't seem to matter whether one calls this "smacking" or anything else. When we hit a child, we are not sending the message we think we are sending at all. We are sending the message that hitting people is a solution.
Children need to grow up with the confidence to think and make choices. If they fear making bad choices (as children who are smacked will eventually), then they will perhaps stop thinking. Waiting instead to be told what to do, and making very little progress unless they are told what to do. Children need to be taught right from wrong, good from bad, but they need to build confidence in themselves and their abilities in order to do this. Smacking, spanking, and etc. are rarely the best first choice.
Well, at first glance, I think of the "spare the rod, spoil the child" Bible verse. There needs to be a healthy balance to life in order to assure a child's success. Without discipline, a child does not learn how to prioritize and work toward something he or she wants. Parents must balance the giving and the working...don't spoil by giving everything without having the child do something to earn it. Ownership...working toward and for a goal...gives a sense of accomplishment and pride. People who are given everything without any investment (for example, government handouts) often do not appreciate what they are given and never become successful enough to stand on their own two feet. A child must be taught tenderly but firmly (which sometimes calls for a smack on the tush) that anything worth having will need to be worked for...material things, food, school and education, job, etc. It all counts.
I don't believe that smacking a toddler for repeated disobedience or serious safety issues is damaging. However, once a child can understand the situation and control himself, it's time for logical consequences. Once a child reaches this age (3 to 4 years old, usually), smacking the child only breeds resentment and encourages the child to hit others to get his way.
I think this depends upon your cultural context and what your alternatives are to "smacking" a child.
If you are in a culture where everyone does smack their children, it may be important to do it as well so that your child does not think that you are lax parents who do not care enough to discipline it.
If you do have other ways of disciplining your child, however, I think you do not need to hit them. Personally, I think that hitting a child is unnecessary and I do not think it helps a child to succeed.
Children need discipline, for sure, but that does not mean that discipline has to come from hitting them.
Think on your own what is the definition of a successful child to you? Really do you believe the quote you have stated? is it acceptable however?
A successful child is one who can achieve the most desired things s/he wants and at the same time can find satisfaction in it. If the child, crossing all sorts of obstacles, can achieve what he wants, and can find amusement in what s/he is doing is definitely a successful child.
A successful child is one who lives his childhood without constraints and shortages of any kind. The development of human consciousness is important from an early age also .
A successful child is one who brings joy and happiness not just to their family and siblings but to all other people that they are in contact with. Children who brighten up the lives of all around them are the most successful.