The earliest scientists were philosophers of the classical period interested in understanding the nature of the material world. After philosophers developed mathematics they were able to apply math to their studies of the material world and discovered measurable consistencies in nature which were eventually called "natural law" or "laws of physics". With the development of the hypothesis-testing-observation method science soon proved to be prodigiously successful. Of note, however, is the fact that people exploring nature through what we now call the scientific method were, as recently as the early 1800's, called "natural philosophers". In other words what we now call science was still universally considered to be a branch of philosophy 2000 years after classical philosophers knew the circumference of the Earth and that matter was composed of atoms and 200 years after the beginning of what we now call the scientific revolution.
What we now call science became so complex, sophisticated and specialized that 'natural philosophers' (except for the polymaths) had no time for any form of philosophy other than science. Around 1830 the term "scientist" was coined to describe a philosopher who worked exclusively in natural philosophy.
The point I wish to make, Stu, is that science is not separate from philosophy, it is philosophy of a special kind - it's philosophy that can prove its hypotheses through testing and measurement and it can do this only because it restricts itself to studies of the measurable.
Popper's falsifiability is and always will be a philosophical concept employed particularly in that branch of philosophy we call science as will another philosophical concept indispensible to science - cause and effect.
is the formal systematic study of the principles of valid inference and correct reasoning. Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science.