Photo by: Ketut Subiyanto What makes two people compatible? Is it mutual physical attraction? Is it sex? Is it that you like the same things, like pizza and basketball? Dictionary.com defines, 'compatibility' as the natural ability to live or work together in harmony because of well-matched characteristics." And according to Scott Petullo of Mystic Twins, "innate compatibility isn’t something you make, but something two people naturally possess." This would mean that true compatibility isn't something you can choose, and it isn't a matter of a couple working hard to make their differences bearable. Instead, true compatibility occurs naturally and you either have it, or you don't. So, how do you know if you're compatible with someone? Below is a list of six factors that exist when you and your partner are compatible. 1. You're physically attracted to each other - Physical attraction is what typically starts the connection between two people.