Now if you see that it is inconceivable that anything should exist, it is evident that at least one inconceivable fact is there. That is to say, that which exists is not limited to the conceivable. Since the inconceivable is there, it is impossible to set any limit to the quantity of inconceivableness which may be present in the situation.
Now were the existence of anything consistently to remind you of the fact of inconceivability, since it is impossible to live without interacting with a large number of existing things, it would be impossible for you to feel in the same way about the conceivable.
Now if anyone were reminded about the inconceivable by the fact of existence at all constantly, he would sooner or later have the perception that there may be inconceivable considerations which are inconceivably more important than any conceivable consideration could be.
Now if you do have a perception that any conceivable consideration may be utterly invalidated by some other consideration which you do not know, and if you are reminded of this perception constantly by the fact that things exist, certain modifications take place in the way you feel about things. These modifications have not taken place in the psychology of most people.
from Advice to Clever Children