Sound of silence

One night at around 11 pm when there was a powercut at my home, sitting alone at a table, doing literally nothing, i was able to hear the sound of silence.

I could feel the emptiness around me and I suddenly felt as if I am not thinking anything.
...absolutely nothing...
just these thoughts came up after a brief silent gap...

How does the heart beat without any instructions?
without any mechanism... or is there a mechanism that i cannot understand?

I know we have scientific reasons for these mysteries...but wanted to think beyond science.

How do i breath? I always breathe without consciously breathing... Times when i am tensed, when catching a bus, when reading a book, when speaking over the phone, when reading this very line, how is that I don't forget to breath? To put it in other words, i need not remember to breath...
I know these are done subconsciously but....What a miracle!
This is also not considered a habit. For instance, when someone asks me what my good or bad habits are, I wouldn't say that my habits include breathing...making sure that I don't forget to miss a heartbeat..... Scintillating!!!
Such mysteries continue to haunt me.

Thank you!