This tweet is meant to prompt you to reflect on your youth in a sentimental way, but I can’t resist seeing it as a time travel puzzle. Let’s nerd out about this!

Prevent a bad decision

The best answer I saw on twitter was “Don’t marry him.” This answer respects the intention of the tweet but is a good literal answer too. I would recommend putting someone’s name in there instead of “him” to prevent any misunderstandings!

Personally, I don’t think many of my bad choices could be prevented with just three words. Maybe we could prevent me from cycling at night in the city without lights on my bike. “Lights on bicycle” might be enough to get the message through. Or “Unlit bicycle accident!”

Prevent a random accident

It should be easy to prevent a random accident if you know when it will happen. If it was a car accident you could ask the driver stay home, or force them to, or even just delay them for a few minutes to change up the random events of the day.

The problem is that you only have three words. If a whole date was one word, I think “Sam crashes 2010-02-13” would be a very effective message! But that doesn’t look like three words to me. I think three words would only get you to “Sam crashes 2010”, which is enough information to make your 18-year-old self extremely stressed but probably not enough to save a life.

I’m having trouble with this one. Even if the accident was tied to a unique event - i.e. your friend Sam had a car crash while going to see the premier of Captain America: Civil War - this is still really hard. “Captain America accident?” I can’t see this working. Sorry.

Save a lot of people

At the risk of getting too serious for a silly post, it would be nice to prevent the 2019 Christchurch attack. This was a mass shooting done by one person. If we could somehow tip off the police, we could prevent the whole thing. But… how?

Just saying the shooter’s name uses up two words. There is no one word that would tell my younger self to wait a dozen years and then ask the police to investigate this guy.

I think the shooter posted about their plans on a public website before the attack. Maybe I could do “[name-of-website] [day] [month]” to get my younger self to check that website on that day every year. Then maybe young-me would see the post, recognise its importance, and contact the police. But there are so many posts, and so many years, and I wouldn’t have any clue about what I was looking for. I don’t think it’s going to work.

Get rich

Of course getting rich is the easy one: “Netflix shares 2020”.

I think young-me would correctly understand that that date was the time to sell, and that I could buy at any point up until then and expect gains.

Being unable to send an exact date is annoying, as there are a few years where Netflix peaks in the middle of the year but comes down again at the end. I could try “Netflix June 2018” but young-me is more likely to look out for some TV to watch than assume I’m sending investment advice.

If the investment was more obviously an investment, I could leave out the second word and put a month in instead. For example: “Bitcoin December 2018”. Bitcoin didn’t exist when I was 18 but past-me would probably connect the dots when he heard about it a few years later.

It’s sad that we started out trying to save lives and make the world better, and now we’re planning to invest in a planet-destroying cryptocurrency. But… being a multi-millionaire wouldn’t be too bad.