Take evolution. One scientist from the past said you just need one example to overturn evolution--a rabbit fossil in the Precambrian. The Precambrian is the time period for single cell life on earth. Finding a rabbit fossil in these rock layers would overturn evolution. Just this one example is all you need. Has anyone found this example to overturn evolution? No.
Take gravity. You just need to see two planets or stars repelling each other one time! Just that one counterexample to overturn gravity. Or, set your pen on the table and watch it levitate. That would overturn gravity.
You make it seem like getting this one example is a snap.
Find me this one example to overturn my arguments.