The sensation of the world's unreality can be explained as the emergence of a state in which the boundary between ordinary perception of reality and elements of fantasy or dream-like experience becomes displaced, resulting in a simultaneous perception of the world as both real and unreal.

Blurring the Lines Between Reality and Illusion

The sensation of the world's unreality can be explained as the emergence of a state in which the boundary between ordinary perception of reality and elements of fantasy or dream-like experience becomes displaced, resulting in a simultaneous perception of the world as both real and unreal. For example, in one described state, when “the indistinct frontier between wakefulness and dreaming has been erased,” a person finds themselves in a mixed state where fantasy and objectivity are indistinguishable. This is experienced as a simultaneous feeling of reality and unreality, that is, an experience where the difference between the external world and inner imagination becomes blurred (source: link txt).

Regarding proofs of objective reality, some arguments indicate that our judgments rely not on copies or interpretations of reality but on the invariant elements of the world itself. As noted in one of the texts, “the objective content of judgment is provided by elements of reality itself, even if the event has separated from us and become part of the past; it forever remains the same.” Thus, the stability and unchangeability of real phenomena, regardless of our subjective perceptions, serve as a strong argument in favor of the existence of an objective reality (source: link txt).

Furthermore, another part of the reflections emphasizes that objective reality represents the logically crystallized part of all existence, the aspect that can be rationally fixed and communicated as independent of our conscious perception. This is yet another argument in favor of the notion that, despite subjective fluctuations and possible states of unreality, the objective world exists and possesses its own independent structure (source: link txt).

Supporting citation(s):
“So, the first state is wakefulness (the use of senses and reason); ... the fifth state is the simultaneous perception of reality and unreality (in fact, it is a mixture of the first and second states, when the distinction between fantasy and reality is not felt)” (source: link txt)

“Meanwhile, for us the question is resolved as follows: the objective content of judgment is provided by the elements of reality itself, not copies of it, not its products, etc. Every element of reality ... forever remains the same” (source: link txt)

“What forms the essence of ‘objective reality’ … – this character of the reality’s self-assertion against us is determined ... ‘objective reality’ is the rationalized, that is, logically crystallized, part of reality” (source: link txt)

Thus, the sensation of the unreality of the world can be explained as a result of a mixing or disruption of the usual boundaries of perception, while the existence of objective reality is confirmed by the unchangeability of the external world’s elements, which underlie our judgments regardless of subjective experience.