> But we did not invent transistors from quantum physics -- we created transistors long before we had an explanation of how they worked, and we have continued to improve and iterate by making advances in material sciences and experimentation, not by applying first principles. Things like blue LEDs were invented by tinkering rather than by solving Lagrangians.

In a similar spirit ships were built, steam engines made and applications of superconductivity imagined long before the objects were understood from first principles. Creation often proceeded theory nevertheless it is still useful for optimizing designs at later stages.