There is no single 'true' theory, only useful models

The authors introduce model-dependent realism: the position that a scientific theory is a mental construct connecting observations, and multiple different models can each accurately describe the same phenomena without one being uniquely 'correct.' Asking which model is really true, independent of any model, is treated as a question without a clear meaning, since we only ever access reality through some model or other.

Their example is describing a goldfish's curved view of the world through a bowl: the fish's physics would look distorted to us, yet could still form a fully consistent, predictively accurate system from inside the bowl. Neither the fish's model nor ours is more 'true' in an absolute sense — each works within its frame.

This reframes classic debates (is light a wave or a particle?) as false dilemmas: both models can be valid depending on what's being measured. Truth in physics is judged by predictive success within a domain, not by matching some assumed single reality behind the models.