Straits Times editor-at-large Han Fook Kwang is largely right about acceptance of immigrant numbers being contingent on the citizens' own sense of security over issues such as jobs, standard of living, healthcare and retirement security (Why immigration isn't a numbers game, Oct 27).

This broadly echoes the view of founding prime minister Lee Kuan Yew, who said that at the end of the day, elections are about jobs, housing and food on the table.

However, successfully gelling as a nation will take more than meeting material wants.

New immigrants could be set in certain ways that are common back home but totally unacceptable here. If efforts at integration are not applied commensurate with immigrant intake numbers, there will be social tensions and lack of cohesion as a nation.

New immigrants may find that there is no need or compulsion to reach out to the other communities because they can organise activities among themselves on platforms such as Facebook. They can live, play and eat among themselves and just interact with Singaporeans on a minimal, need-to basis, like in the workplace.

This is very unlike the pre-World War II days, when my grandparents, newly arrived from China, and various other communities had to live together and even picked up other languages to ease communication.

Over time, we have become cognisant of one another's practices and sensitivities. Once, a new immigrant lamented to me about the "troublesome" dietary restrictions of a certain community - which did not surprise me, considering he is from a homogeneous race country.

In short, the Government cannot just look at hard data, plant a certain number of immigrants, and assume it's going to work. Left unchecked, the process may produce segregated groups that do not co-exist well with one another.

Peh Chwee Hoe