Watch these videos. Pay attention to the discussion of the difference between the terms theory and evidence and the discussion of the reasoning method called Ockham's Razor (also sometimes called Occam's Razor).
This series contains two videos.
Source: Ask a Physicist, https://www.youtube.com/watch?v=ZlCITgODZDw, https://www.youtube.com/watch?v=VczsTuEPMRs
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