It's a reasonable question, if your intuition comes from engines and muscles, where every intentionally applied force must have a power source.

My point is that if you ask an incoherent question (i.e., think of gravity as an agent) you're bound to get an incoherent answer.

But few physics departments with decent instructors. And, as you well know, good scientists are not necessarily good teachers.

At the rate at which the number of countries with apparently no good physics teachers is expanding, given the other comments in this thread, there will be nowhere to study physics on Earth by tomorrow.