When vision memory and the power of suggestion work together

After examining the exquisite gravel for quite sometime near a factory at 2am whilst having a picnic we decided it was probably time to pack up our things and keep walking. We were miles from home and it would be starting to get light soon . It was then that we both noticed the Bedouin tribesmen who were gathered around a campfire chatting enthusiastically about ten meters away from us. “how long have they been there.” I asked my brother. “I don’t know“ he replied. We couldn’t decide if they had been there when we arrived, or if they had turned up since. After much deliberation and not wanting to appear rude but equally not wanting to spoil their evening we decided that the best course of action was to pack up out picnic then as we got up to leave walk over to the tribesmen and say we did notice you guys there but did not want to disturb you, have a nice evening guys. and leave. The Bedouins were still chatting away to each other gesturing and deep in conversation. So we packed up our picnic and headed towards them. but when we got within a few feet of the group it turned out to be just a pile of bin bags. This is funny because everything in this image is a pretty accurate depiction of reality except for the group of bedouin tribesmen. Both of us were seeing the tribesmen as clear as can be chatting away 19 to the dozen around their campfire, one of us had hallucinated them from memory or imagination and the other through the power of suggestion but both of us could clearly see the group of bedouin tribesmen at 2am whilst having a picnic in an unbuilt industrial estate.