The minute I turn off the light, the race is on. I am plunged into darkness, and I am terrified. The switch is on the opposite side of the room from my bed, so I scamper across the floor, tripping over untied sneakers and stubbing my toes on broken printer parts (my roommate and I have managed to go through three printers); the pain is nothing compared to the fear.

I can finally breathe normally once I’m immersed in my covers up to my ears, but even then each sound is a threat. Everything even remotely scary—that trailer I saw this summer for a horror movie, the article about the missing girl and the creepy circumstances around her disappearance, even a disturbing video clip about postpartum psychosis we watched in psychology—comes to mind, where it settles in for a nice visit.

Those rice cakes on my dresser? The gnarled, sinister hand of the mother who drowned her five children in the bathtub. The closet door, made of crinkly plastic? The entrance to the cubicle where a serial killer clown is waiting for me to close my eyes. Even the sliver of darkness beyond the window shade makes me shiver, for I imagine that a white face will be leering at me whenever I open my eyes.

Shifting positions is a horrible inconvenience, because each time I do I need to make sure that my ears are covered (it’s a rule I have; it’s totally nonsensical, though, because in the dark, hindering your sense of hearing is no joke). I try to get myself to think of the probabilities, not the possibilities, but to no avail: every door slam makes me jump, and the jolt of an incoming text message is enough to make me leap out of bed and take a lap in the nicely lit hallway.

Being scared of the dark is uncomfortable in circumstances in normal life, but the college environment is an unpredictable one with new obstacles and predators, such as people who wish to save the planet by installing light timers. I was once in the shower when the automatic lights went off; I must have been in there for ten minutes. A silent scream rose in my throat, and I frantically waved my hand around to prompt the sensors into action.

There’s something about the dark that’s so much more terrifying than the light, and the reason is quite simple: I can’t see clearly, and my sense of control is thrown. Thinking about it scientifically, the absence of photons—light particles—should make it no more likely that a murderer will be hiding in the closet, or that a hand will reach up from the enormous crack between my bed and the wall and snatch my toes, but the problem is that there’s no way to be sure.

Darkness alerts all my senses and signals the onset of hysteria. It gives my overactive imagination license to make mauled, bashed-in ghosts out of gym bags and wide-eyed, decaying corpses out of my roommate’s doughnut pillow (that thing is as creepy as Carrie). “Pareidolia” is the word for giving meaning to everyday objects, and in darkness I have an acute case of pareiphobia.

Because, in many ways, I am a senior citizen, I go to sleep rather early, and remain on alert until I hear my roommate click the door open. At this point, I let out a sigh of relief. For some reason, the minute another human enters the room and begins to get ready for bed, things retake their normal shapes and I’m able to let my guard down. It’s not only that she is abler-bodied than I to defend us against a murderer (because she totally is: she’s training to become an EMT), but also that once she’s there I have somebody to share the burden with: being aware of the room is no longer completely on my shoulders.

It was the same way back at home, when I shared a room with my sister: though I doubted she would be any more likely than I to tap into that illusory superhuman strength that comes with a fight-or-flight response (yeah, right—both of us would be supremely easy victims for even the dimmest-witted of murderers), but having another body in the room made it so that I wasn’t on surveillance duty alone.

I’m at my most sociable in the dark, I guess. Humans are creatures that need each other; they have evolved to live in groups for their own protection. It’s a fact that I know is true but don’t always believe in daylight. There are times, from sunrise to sunset, at which I’d rather hide under my bed than deal with people. (Call me antisocial; I prefer “introverted.”)

But darkness brings us together, if for no reason other than survival. It brings out something primitive. Darkness keeps us inside, together as families or roommates or cohabitors, while the creatures of the night (murderers, coyotes, wild boars, Lord Voldemort, Joan Crawford’s ghost, and Ann Coulter) roam free. We know our human fallacy—visible light is the only light that we can see, and our senses of hearing and smelling are relatively poor—and in the darkness we crowd into collective huts, houses, cabins, and dorm rooms to stay safe. No matter how independently we roam by day, come nightfall we retreat to shared spaces. Why? Because we’re scared of the dark.

It’s a vestige, sure. But without it, we risk losing the last stretch of the 24-hour day when we need each other. Braver, it turns out, is not always better.

Davis is a member of the class of 2017.