Science Quote by Niels Bohr

Bohr’s line lands like a clean little act of sabotage against common sense: the world feels solid, so why is its foundation made of entities that refuse solidity, location, even intuitive “thingness”? The intent isn’t mystical; it’s disciplinary. Quantum theory didn’t just add weird facts to physics, it rewired what counts as a fact. Bohr is warning that “real” is not a photograph of nature, it’s a negotiated outcome between measurement, language, and the experimental setup.

The subtext is a rebuke to naive realism, the comforting idea that objects possess properties the way apples possess redness, independent of us. In Bohr’s Copenhagen posture, an electron isn’t a tiny marble with a secret itinerary; it’s a set of probabilities that harden into a result only under specific questions we know how to ask. “Cannot be regarded as real” points less to nonexistence than to the failure of classical categories. The underlying constituents are real enough to ruin your predictions if you ignore them; they’re just not “real” in the everyday, picturable sense.

Context matters: Bohr is speaking from the early-20th-century crisis where Newtonian intuition broke on the shoals of Planck, Einstein, and Heisenberg. His rhetorical power comes from reversing the hierarchy. We usually treat atoms and particles as the bedrock that explains tables and trees. Bohr flips it: the table is the stable story; the bedrock is the unstable grammar. It’s a line that flatters no one’s gut instincts, and that’s the point.