"Two masses attract each other with a force F = m1 m2 G/r^2" "OK, but why don't they repel each other?" "That would make life really hard, and we wouldn't be

"Two masses attract each other with a force F = m1 m2 G/r^2" "OK, but why don't they repel each other?" "That would make life really hard, and we wouldn't be here discussing it ..."