I believe I am ever so slightly psychic. This is due to several little, trivial things which have happened over the years, and to one big thing which I will relate here.

It was 1989. I was 19, and I had a summer job as a page at the public library in Ada, Oklahoma. At the time, Ada had a population of about 20,000. The library is a decent size, maybe an acre. It's a single large open space, slightly split-level, with the checkout desk smack in the center. Because of the central desk, shelves, columns, and the split-level, it's impossible to see the entire library at any one time, despite the open space.

I was one of two people working Saturday morning, and it was a slow, sunny day. On Saturdays at the time, we closed at 1:00 in the afternoon. As closing time approached, I toyed with the idea of staying after hours to browse the books in perfect solitude. I didn't plan to ask permission, but I also knew that no one on the library staff would mind if they knew. Doing it without telling anyone was just easier.

There was a second reason I felt like staying after closing time. An odd feeling was slowly coming over me, as if I should stay after closing. I ignored this feeling, registering it only subconsciously, dismissing it because there was no basis for it. The real reason I wanted to stay after closing was to browse the shelves. This wasn't a lie I told myself to rationalize the strange feeling; I really did want to browse the shelves, and I would have stayed, anyway, even if the feeling hadn't existed.

At 1:00, my coworker and I ushered the final few patrons out the door and turned out the lights. As a lowly page, I had no authority, so I didn't even have a key. My coworker locked the doors, then we parted. She left through the front door, I was supposed to leave through the back. But I didn't. I watched her leave, and stayed put.

Even though the lights were off, the entire wall facing the street was nothing but huge windows which let in plenty of sunlight, so it was still very easy to see.

Each door, front and back, had a large push handle which allows a door to be opened from the inside even though it is locked from the outside. I could stay as long as I wished, and when I was finished, all I had to do was exit the building and the door would shut behind me, locked.

I was free to head straight for the stacks and indulge my inner bookworm. But I didn't.

The strange feeling which had been growing over the past half hour became my dominant emotion, and for no reason I can explain, I instead walked very quietly to stand behind the central counter. I stood there, perfectly silent and still, waiting. What was I waiting for? I was waiting for the patron who had secretly stayed behind to reveal himself. I have no idea how I knew a patron had stayed behind, but somehow, I did. This incredible, bizarre feeling was justified a few seconds later when I heard his footsteps.

He came out of the stacks. He had hidden deep in the stacks when the library closed, and now he was heading directly towards the central desk with a sure and purposeful stride. The desk where we kept the cash in a till.

He got about five feet beyond the shelves, into the open, when he registered that there was a person standing at the central desk, watching him silently. I didn't say a word.

He did a magnificent guilty double-take, completely caught off guard, and stopped. Then he awkwardly looked around and said as innocently as he could, "Oh...oh...are you guys closed?"

"Yes, sir, we are closed," I said.

"Oh...oh...okay," he said, and awkwardly fast-walked to the front door and let himself out, trying hard to look like he wasn't hurrying.

I have no idea who he was. I didn't call the police, as there was no point; I couldn't prove he was up to no good.

The following Monday, I told the librarian what had happened.

Whenever I think about that day, I wonder about my incredible intuition.

As I see it, there are two strange facts which need an explanation:

1. At 12:30, I somehow knew half an hour in advance that something wrong was going to happen and that I needed to stay (even though at first I ignored this feeling).
2. At 1:00, I somehow knew, beyond a shadow of a doubt, that someone was hiding in the library and was about to come out, and I knew it fifteen to thirty seconds before I heard the footsteps.

I can think of three non-psychic explanations:

1. It's vaguely possible that my subconscious brain noted the man a few minutes before closing and knew he was unaccounted for when everyone walked out the door. But that's not how my brain works (I wouldn't notice a snake if it were in front of me), and it doesn't feel true. This explanation also doesn't account for the fact that the strange feeling began about 12:30.
2. I know I didn't subconsciously hear him breathing as he hid in the stacks at closing time, as I would have had to hear him from at least a hundred feet away. Even if I did, this doesn't account for the fact that the strange feeling began about 12:30.
3. It's possible that the man was nervous when he arrived, planning ahead of time to rob us, and I encountered him around 12:30 and subconsciously picked up on his nervousness. This would account for the strange feeling ahead of time, but it's a real stretch. Also, this would only have given me a general feeling of unease, yet my intuition was specific. Therefore I find that this explanation does not work.

Each of these non-psychic explanations has a very low chance of accounting for one or the other of the strange facts, but none of them account for both facts.

It's possible that it could be a combination: perhaps explanations 1 and 3 are both true. That would fit the facts, so logically, I must concede this possibility. But I find it highly improbable, and it just doesn't feel true, because again, I know how my brain works – especially at 19, when I was so wrapped up in myself that I only noticed people when they impacted my world directly.

I believe I experienced a psychic premonition. I don't have the vocabulary to describe the feeling to someone who hasn't experienced the same thing; I can only say that it came upon me like nothing before or since. It almost felt as if an external power were whispering to me, "Stay, be quiet. There's someone else here." This external power (if it existed) was certainly not controlling me, but the urge to do as it said was powerful.

It seems, to a lesser degree, much like a person who commonly flies, yet refuses to board a particular aircraft due to an inexplicable feeling of dread, only to learn later that the aircraft crashed. And yes, I know absolutely of at least one instance of this happening.

I've never experienced another major psychic phenomenon, before or since. So far, that Saturday morning in 1989 is a one-off experience.