First of all, the situation surrounding the previous and the new Caleb(s) shows how important a person's name is to the community. There is value for the individual through the respect shown towards one's life as shown through the Murmur-of-Replacement ceremony as well as the Ceremony of Loss (44). It is wonderful that the community grieves together when the first Caleb is lost and then they celebrate together when a new Caleb is introduced. It is also respectful and wonderful to know that there is no other person in the community who has another's name while one is living. For example, Jonas knows that he is the one and only Jonas in town. People won't get confused as they discuss each other and celebrate in each other's successes. This gives a person a great feeling to know that they are valued as the only Jonas, or the only Caleb, in the community.
On the other hand, once a person passes away, the name can be reused for another person later. Some might say that this devalues the life of the first person who had the name. One might also argue that it would be easier to forget the first Caleb as the second Caleb lives and creates new experiences associated with his life. There also doesn't seem to be any last names present within the community, so a family's name is not perpetuated throughout history. That's significant because last names would create memories of those who have gone before and that is exactly what the Receiver bears so the rest of the community won't suffer under memories.
So, is a replacement Caleb a good idea? For the purposes of Lowry's society, yes, the second Caleb is needed in order to replace the feelings of grief and loss from the first Caleb. The whole point of the society is to have peace every day without the pressures, stress and pain felt from memories. For our society today, however--no! Replacing a child with another one would seem barbaric. That would make us seem like inhuman monsters. Today, we value everyone as an individual and don't want to forget anyone--especially a child who wandered off and died.