Yes I can show you definitive proof. To do so I'll use another Scientists - Nikola Tesla.
"The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence." - Nikola Tesla
How is that definitive proof of making scientific discoveries by studying philosophy and metaphysics?
Nikola Tesla was a great scientist, true. But I would be comfortable in saying that all of his discoveries were based off of physical observation and experimentation and not due to philosophy and metaphysics.
EDIT: and it bears stating that in the past century there were decades where more scientific progress was made than in all the previous centuries...and that was without resorting to philosophy or the study of metaphysics.