The thing is, it is not necessary to know everything to the last possible degree -- it is quite often quite enough to have sufficient depth of knowledge to predict what will happen. Sure, I can't tell what every last force exerted by whatever sorts of energy might be in the room to know -- with absolute certainty -- that short of an earthquake, building collapse, plane hitting the house or my action, that my coffee table is not going to suddenly jump up and land in the dining room.Knowledge can be based on observations of the 'objects' around us, but that does not make the knowledge 'objective'. in fact, there is no such thing as 'objective knowledge' because all knowledge is subject to the limitations of the holder. We are the subjects and everything we know or don't know is relative to that (is subjective).
We can sit in a room and look at the walls and the ceiling and all the objects in it and tell ourselves that we understand everything about that environment. We know all about how it was made and what it is for and why it exists. And yet there are forms of matter and energy in that room that our bodies cannot detect. And that interact with each other and with the forms of energy in the room that we can detect in ways that we know nothing of. And there are many questions that can be asked about the existence of that room that we could not possibly answer.
But we pay all this mystery no mind. So that in our minds we can feel that we know what it's all about. And can therefor anticipate and control things to our own advantage.
But ignoring our ignorance does not result in increased knowledge even though it may feel like it. And even though we may really want to believe it.
In other words, knowing enough is quite often enough, and it is bootless to fuss about stuff you can't know.
That is why @TagliatelliMonster's pet dragon is such a useful metaphor -- because you know quite enough about it to know that you will not be affected by it in any manner, and can therefore dismiss it out of hand.
For many of us, that is equally true of whatever it is that people suppose they mean by "God."