Einstein acknowledged that philosopher David Hume recognized the limits of our ability to derive certain concepts, such as causality, solely through logical reasoning based on our experiences. Hume's insights pointed to a key philosophical quandary: our understanding of cause and effect cannot be fully explained by what we observe, challenging traditional views of knowledge acquisition.

This perspective is often associated with positivism, a philosophy that rejects the legitimacy of ideas that extend beyond empirical experiences. In this view, knowledge is grounded only in what can be directly perceived, leaving abstract concepts unsupported by observable evidence outside the realm of validity.