My daughter, who lives in California, asked me to explain why it's bad to have a mirror facing you when you sleep.
She said she just bought a dresser with a mirror which faces the bed. She said she didn't want the mirror installed because she would have nightmares, but her American husband wanted it included. So she just covered it at night. Her husband thinks it's mere superstition to believe mirrors in the bedroom are bad.
I only know one reason why it's considered bad to have a mirror facing the bed. It is connected with the projection of our astral body when asleep, but I found a more detailed discussion of the subject online by a feng shui specialist named Victor Cheung in July 2017. Here's a summary of his detailed presentation:
1. It depletes personal energy and creates sleeplessness.
This is because "the mirror doubles and bounces all sorts of energy. It disrupts the tranquillity needed in a bedroom for better sleep." I'm not sure if this is true, but no harm in complying.
2. It brings nightmares.
"When we sleep, our soul (i.e. astral body) leaves the (physical) body. When the soul sees its own reflection, it gets startled, hence the bad dreams and nightmares… When the soul returns to the body, it may mistake the image in the mirror from the real body, hence the saying 'soul-stealing.'" There is some evidence for the existence of the astral body, and that it travels out of the physical body during sleep.
3. You will be alarmed by movements.
"According to the researchers at Washington University School of Medicine in St. Louis, our eyes detect movement through a neural circuit in the retina at the back of our eyes.
"Our attention is naturally attracted to whatever moves, whether they are in front of your eyes or in the corner of your eyes… So if you have a mirror next to you when you sleep, you will notice any movement from the mirror's reflection." This may be true only if there's light in the room, and if your eyes are slightly open when asleep.
4. You may scare yourself.
"When we suddenly wake up from sleep, we might scare ourselves when we see our own reflection in the mirror." This is possible.
5. Something green in colour might be seen.
"Because most mirrors are not 'perfect mirrors,' you may sometimes see a bit of green in the reflection. And this may startle you. Mirrors do not reflect the full spectrum of light."
6. You may hear strange sounds.
"Mirrors aren't just for reflecting lights and images, it is also for reflecting sounds… The sound is considered a type of 'Qi' in feng shui, and mirrors bounce the sound back into the room as opposed to just absorbing it." And this may affect the quality of your sleep.
How to remedy these problems:
"Just cover the mirror facing your bed with a cloth, so it doesn't reflect you and your bed."
As a last word of advice: Not all react the same way to having mirrors in their bedroom. If you are not bothered at all by a mirror facing your bed, you don't have to do anything about it. As the saying goes, "If it ain't broke, don't fix it."