Solipsism

Solipsism (ⁱ/ˈsɒlᵻpsɪzəm/; from Latin solus, meaning 'alone', and ipse, meaning 'self') is the philosophical idea that only one's own mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure; the external world and other minds cannot be known and might not exist outside the mind. As a metaphysical position, solipsism goes further to the conclusion that the world and other minds do not exist.

There are varying degrees of solipsism that parallel the varying degrees of skepticism:

Metaphysical solipsism is a variety of solipsism. Based on a philosophy of subjective idealism, metaphysical solipsists maintain that the self is the only existing reality and that all other realities, including the external world and other persons, are representations of that self, and have no independent existence. There are weaker versions of metaphysical solipsism, such as Caspar Hare's egocentric presentism (or perspectival realism), in which other people are conscious but their experiences are simply not present.

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