you can't see the wind blowing but we can feel it and we see leaves blowing around , so u have to use ur imagination and also have faith that something can be there and we just have to see it or feel the wind, so believe and you will see ,
Something exists if it causally interacts with something else that exists. We know it will exists if the chains of interaction lead to our senses.It will be answered by saying something object of our senses.
