𝑺𝒐𝒍𝒊𝒑𝒔𝒊𝒔𝒎 𝒔𝒚𝒏𝒅𝒓𝒐𝒎, refers to a psychological state in which a person feels that reality is not external to their mind. 𝘐𝘯 𝘰𝘵𝘩𝘦𝘳 𝘸𝘰𝘳𝘥𝘴: the feeling of being the only real person. the feeling of everything but yourself being made up in your mind. 𝗘𝘃𝗲𝗿𝘆𝘁𝗵𝗶𝗻𝗴.