Have you already thought about the difference between these two developments? Today I gonna write about it basing in a speech given last week by my Si Fu, Senior Master Julio Camacho. He wanted to explain to the practitioners that the center of this differentiation between Personal and Humanity is in the Chinese ideogram that means "humanity" (人).
In these two traces in 人 is explicit the necessity of two persons for the construction of humanity. An alone person cannot form humanity, there are so many things, centrally generated by the variation of the point of view, that an alone person wouldn't replace. Thus, is a requirement for the Human Development the relationship between two persons. Another conclusion we can get from the ideogram is that the basis of Human Development is in relation between two humans at a time. Even in an ambient with hundreds of people, I only can practice my humanity one by one.
Otherwise, if I want to develop myself, not necessarily I should search another to achieve my goal. Is possible to obtain Personal Development by reading a book, viewing a movie, writing something about Ving Tsun, taking pictures, at the gym etc. By all means, the necessity of another human is implicit in the context, because I can't read without a book written by someone or write a letter without a computer or paper, equally made by someone or many others. However, the other people aren't in the same real situation that I live in the moment that I am developing myself. Although the presence of the other is a requirement, it is not at the same time. Because of it, making any of these things I develop myself as a person, not like a human being.
This explanation given by my Si Fu was not to convince the practitioners that one type of development is better than another. The division made by him I believe was to provide the capacity to the practitioners exploring with more intelligence these two types of development.