No, I can't. Gravity is a miracle. It is supernatural. Now, as for 1 + 1 = 2, that, as a primary student of the mathematical sciences, I can prove.
Really? It took Russell and Whitehead about 800 pages of proof, starting with Peano's axioms reach that point. Please don't do it here. (Oh, and by the way, they actually got it wrong--a fact that wasn't noticed until a grad student found the flaw about 50 years later).