Solipsism : Thesis to the
effect that only I exist (from the Latin: "solus" = "alone" and "ipse" =
There are often distinguished three different main
senses of solipsism: Ethical, metaphysical and epistemological.
One is solipistic in the ethical sense if one is an
egoist, in theory or
practice; one is so in the metaphysical sense if one believes there
exists nothing but oneself; one is so in the epistemological sense if
one holds that all one really knows is one's own experiences and
To use "solipsism" for "egoism" seems mostly confusing, and hence
this meaning will not considered here.
Solipsism in the metaphysical sense has been put forward by some
philosophers, but usually not in a very serious way. One serious problem
the doctrine has, if true, is that it hardly can be stated using ordinary
natural language, for the reason mentioned below, when discussing
solipsism in the epistemological sense.
Solipsism in the epistemological sense has been put forward by many
philosophers, starting with Augustine and Descartes, both of whom
considered the argument "cogito ergo sum" (I think, therefore I am -
with the suggestion that conversely all I am is what I think) and -
Augustine - "fallor ergo sum" (I make mistakes, therefore I am). In
either case, the suggestion is that one's self must exist, but the
existence of anything else is dubitable.
The reason epistemological solipsism has some importance is that all
human knowledge and belief, whatever it is about, starts in the
experiences of some human individual, and indeed may never get further
than that in cases of mistaken beliefs, fantasies,
The reasons epistemological solipsism is hard to take seriously are
mostly of three kinds, of which I first state the fundamental one.
(1) To reason at all one must make
assumptions, and indeed make assumptions of things that go beyond
one's own present experiences. For if one does not do so, one cannot
even test one's guesses. (See:
(2) No human being has been raised as a solipsist: Everybody has been
raised by other persons who believe that there are other persons with
experiences like themselves, whatever else they believe. (See:
(3) Natural language is full of many terms whose standard
are not consistent with solipsism, for it is full of ordinary terms that
assume the existence of other persons and their experiences, and of
things that exist before, after or beyond one's experiences of them.
(See: Minimal metaphysics)
Even so, solipsism is philosophically important because it states an
extreme and minimalistic thesis - again: only I exist, only my
interests, beliefs, experiences exist, there is nothing (that is
certain) other than me and myself - that few if any sane persons
really believe, and that therefore all avoid by making assumptions that
go beyond it, which usually also are not very well-founded.