Final answer:
Max Black suggests that if two entities, such as a twin world and no-twin world, cannot be empirically differentiated, they are indistinguishable and therefore identical, reflecting post-modern views of reality and the limits of human epistemology.
Step-by-step explanation:
Max Black's assertion that there is nothing verifiably different between the twin world and the no-twin world stems from a philosophical interpretation of identity and indiscernibility. According to this perspective, if no empirical differences can be observed or verified between two scenarios or entities, they are indistinguishable and, therefore, identical. This aligns with post-modernism, which questions objective knowledge of reality, suggesting that what we perceive as reality (reality 1) is just a construction of our beliefs and experiences (reality 3). The dream argument further supports this by showing how our perceptions can be deceived, as dreams feel real while we experience them, questioning our ability to distinguish between actual reality and perceived reality.
Additionally, Immanuel Kant's critique of the concept of existence as a predicate challenges the notion that just because we can conceive of something in our minds, such as God or the perfect island, it must exist outside of our mental construct. Similarly, Leibniz argues that without an infinite perspective, humans cannot conclude the absolute nature of our world or reality. In this vein, Black's assertion highlights a fundamental limitation in human epistemology—the impossibility of proving or disproving the existence of certain phenomena or realities strictly through empirical observation. Hence, the discussion about realities becomes inherently bound to our subjective experience and understanding.