The word "predictable" implies "deterministic", but they are not identical. The universe can be governed by strong deterministic laws, while being too complex to simulate and thus predict.
This poses some difficult questions for science, given that most science up to now has been about predicting something, trying it and checking whether theory and practice matches.
Right, but I took the comment in the OP to mean that non-Newtonian physics makes things 'non-deterministic', even is we leave aside the practicality of simulating the universe at the molecular (or smaller?) level.
This poses some difficult questions for science, given that most science up to now has been about predicting something, trying it and checking whether theory and practice matches.