Nor are we overly skeptical about the reality that comes to us through the five senses. We know what we see. We know what we have heard, or touch or taste or smell. Though we also know that these senses don't tell us everything. What we do have difficulty understanding is direct knowledge that comes not through conversation, nor through normal thought processes, nor through the five senses.
Mystical experience is such direct knowledge.
The religious concept of revelation is also such direct experience. Most of us believe that if we could only pray hard enough or concentrate deeply enough or meditate long enough we would come to this direct knowledge. But we live in an age where this is difficult to accomplish. We are all in a hurry. We are surrounded by noise.