Personalism: The assumption
that there are other persons like oneself.
This is an assumption, and indeed a
metaphysical one (See:
although it also is an assumption nearly all human beings make, and
acquire while growing up.
Even so, the experience of other
human beings - supposing there is no ESP - is
forever hidden to any human being, and exists
imaginatively, by assumption, and by
education, and is not given as one's own
experience is to oneself: The actual
feelings, beliefs and
desires of others are as private to them
as one's own feelings, beliefs and desires are private to oneself, and apart from
analogy and, possibly, instinct, the main
reason one attributes feelings, beliefs and desires to others seems
to be years of education by others who made that assumption and treated
and educated one on the basis of it.
Also, a large part of what one believes and feels oneself
to be, and of what one does or may attribute to others, is based on
language, that enables one to have and mentally use all manner of
ideas and distinctions one either could or
would not have without language, or that are far less easy to have or
think about without language.