Sometimes I wonder if those mosquito mat thingies really work or if the effect if just psychological. Like, you know you've put something out to repel ze mozzies, so your brain relaxes and you're able to go to sleep. After all, the brain is a very powerful organ.
I wonder the same about many other things. Like, are those medicines really efficacious or did I just trick my brain into thinking they are, which is why I feel better? How much of what we perceive and experience is real, and how much just imagined?