Solipsism
Solipsism (/ˈsɒlɪpsɪzəm/ ⓘ SOLL-ip-siz-əm; from Latin solus 'alone' and ipse 'self')[1] is the philosophical idea that only one's mind is sure to exist.
Epistemological solipsism is the variety of idealism according to which only the directly accessible mental contents of the solipsistic philosopher can be known.
Methodological solipsism sometimes goes even further to say that even what we perceive as the brain is actually part of the external world, for it is only through our senses that we can see or feel the mind.
The methodological solipsist believes that subjective impressions (empiricism) or innate knowledge (rationalism) are the sole possible or proper starting point for philosophical construction.
Well-known frameworks such as Descartes' epistemological enterprise brought to popularity the idea that all certain knowledge may go no further than "I think; therefore I exist.
(See Brain in a vat) Some philosophers hold that, while it cannot be proven that anything independent of one's mind exists, the point that solipsism makes is irrelevant.
[9] One of the most fundamental debates in philosophy concerns the "true" nature of the world—whether it is some ethereal plane of ideas or a reality of atomic particles and energy.
Materialism[10] posits a real "world out there", as well as in and through us, that can be sensed—seen, heard, tasted, touched and felt, sometimes with prosthetic technologies corresponding to human sensing organs.
Dualists then attempt to identify attributes of mind that are lacked by matter (such as privacy or intentionality) or vice versa (such as having a certain temperature or electrical charge).
The idealist philosopher George Berkeley argued that physical objects do not exist independently of the mind that perceives them.
[18] Rationalism is the philosophical position that truth is best discovered by the use of reasoning and logic rather than by the use of the senses (see Plato's theory of forms).
Christian List argues that the vertiginous question and the existence of first-person perspectives implies a "quadrilemma" of metaphysical theories of consciousness.
[25] According to Popper: a hypothesis that cannot be falsified is not scientific, and a solipsist can observe "the success of sciences" (see also no miracles argument).
One critical test is nevertheless to consider the induction from experience that the externally observable world does not seem, at first approach, to be directly manipulable purely by mental energies alone.
One can indirectly manipulate the world through the medium of the physical body, but it seems impossible to do so through pure thought (psychokinesis).
It is simply poor reasoning when considering pure idealized logic and that is why David Deutsch states that when other scientific methods are used also, (not only logic), solipsism is "indefensible", also when using the simplest explanations: "If, according to the simplest explanation, an entity is complex and autonomous, then that entity is real.
[26] A solipsist's investigations may not be proper science however, since it would not include the co-operative and communitarian aspects of scientific inquiry that normally serve to diminish bias.
Many people are intuitively unconvinced of the nonexistence of the external world from the basic arguments of solipsism, but a solid proof of its existence is not available at present.
Some developmental psychologists believe that infants are solipsistic, and that eventually children infer that others have experiences much like theirs and reject solipsism.
[27] The earliest reference to solipsism is found in the ideas in Hindu philosophy in the Brihadaranyaka Upanishad, dated to early 1st millennium BC.
For the enlightened, all that exists is nothing but the Self, so how could any suffering or delusion continue for those who know this oneness?The concept of the Self in the philosophy of Advaita could be interpreted as solipsism.
Similarly, the Vedantic text Yogavasistha, escapes charge of solipsism because the real "I" is thought to be nothing but the absolute whole looked at through a particular unique point of interest.
[31] Yoga Vasistha - Nirvana Prakarana - Uttarardha (Volume - 6) Page 107 by Swami Jyotirmayananda Samkhya philosophy, which is sometimes seen as the basis of Yogic thought,[32] adopts a view that matter exists independently of individual minds.
Having established this distinction between the external world and the mind, Samkhya posits the existence of two metaphysical realities Prakriti (matter) and Purusha (consciousness).
Mahayana Buddhism also challenges the illusion of the idea that one can experience an 'objective' reality independent of individual perceiving minds.
[35] In other words, even though a chair may physically exist, individuals can only experience it through the medium of their own mind, each with their own literal point of view.
Some later representatives of one Yogacara subschool (Prajñakaragupta, Ratnakīrti) propounded a form of idealism that has been interpreted as solipsism.
Bertrand Russell wrote that it was "psychologically impossible" to believe, "I once received a letter from an eminent logician, Mrs. Christine Ladd-Franklin, saying that she was a solipsist, and was surprised that there were no others.
