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What obvious adult discoveries made you feel a bit of a plonker?

691 replies

Airconfan · 21/09/2026 00:36

What’s something you learnt as an adult that made you think that’s completely obvious and yet I have never considered that….i feel like a bit of a plonker?

Mine was when taking tablets, the more you drink with it the better it will dissolve. I think alot of tablets are testing with the assumption people will drink 250ml alongside it.

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EvieBB · 21/09/2026 10:22

Bananavibez · 21/09/2026 03:19

That you dont rinse your mouth out after brushing your teeth

What? I always rinse. Are you not supposed to?

0906795m · 21/09/2026 10:24

unlimiteddilutingjuice · 21/09/2026 08:21

Oh my God, so many things:

  1. The lockabie bomber was an Islamacist named Almagrahi. Not, as I had always thought, an Irish republican named Al McGarry.
  2. There is no battle in Scottish history called Fulluden. Therea a Culluden and a Fludden which I was conflating into one thing.
  3. There was never a police Nessy in the kids TV show Family Ness, named Elliot Ness. I have a very clear memory of this happening, but as far as I can find out, it never did. No idea why my mind made this up for me.
  4. Police dogs in the US are not trained to leap in front of bullets to save their handlers. I thought this forever because of a line in Turner and Hooch about Hooch dying because he was "doing his job" which i now understand was meant figuritively.

Al McGarry and Fulluden made me laugh out loud! Thank you 😂

Isabella70 · 21/09/2026 10:24

Mulledjuice · 21/09/2026 10:17

both, i think - the sun and the moon both exert a gravitational pull and the earth rotates into one and out of the other.

The sun and the moon (but mostly the moon) principally (and when the sun and moon line up is when you get spring tides).

But the rotation, and the inertia of the water, do have an effect - for example the bulge at high tide is actually a little bit ahead of the moon's position.

Mulledjuice · 21/09/2026 10:26

Isabella70 · 21/09/2026 10:24

The sun and the moon (but mostly the moon) principally (and when the sun and moon line up is when you get spring tides).

But the rotation, and the inertia of the water, do have an effect - for example the bulge at high tide is actually a little bit ahead of the moon's position.

yes, it wasnt me who said the earth's rotation was irrelevant

HardStopAt4 · 21/09/2026 10:26

I found out fairly recently that currants (the dried fruit) are not actually dried blackcurrants, as I had assumed they were.

Thewonderfuldollypartonsbra · 21/09/2026 10:27

StormInaDcup99 · 21/09/2026 10:03

I only found out fairly recently that the term blow job is a shortened version of below job ie b'low job!

I take it back-ive learned two new things today!

I have to admit to gently taking the piss over the years but she takes it in good humour

I'll have to tell her this-thank you!

Isabella70 · 21/09/2026 10:27

Mulledjuice · 21/09/2026 10:26

yes, it wasnt me who said the earth's rotation was irrelevant

Sorry if I misrepresented you Mulledjuice

CitizenZ · 21/09/2026 10:28

I used to think Dubstep was a band. I was confused that I had never seen them yet lots of people talked about them. and in my head they were kind of the Banksy of music. I had to google it to find out it was a genre.

x2boys · 21/09/2026 10:30

HardStopAt4 · 21/09/2026 10:26

I found out fairly recently that currants (the dried fruit) are not actually dried blackcurrants, as I had assumed they were.

What are they then?
I get mixed up with currents ,raisens and Sultanas .

Shedmistress · 21/09/2026 10:32

Seziah · 21/09/2026 09:53

Ah but cucumbers bred to be small are still small cucumbers, I would say! But I know what you mean, they’re not young normal-sized cucumbers

Its like - green tomatoes are not unripe red tomatoes, they have been bred to be green when ripe.

Green peppers are often unripe red peppers, but some peppers and chillis have been bred to be ripe when green, or yellow and some ripen to purple. Some are purple the whole way through and are only really ripe when the inside turns red.

Yet you can stil eat any pepper unripe or ripe. Ripeness is about maturation of the seed not the fruit.

It really is not the case that gherkins are just small cucumbers.

Isabella70 · 21/09/2026 10:32

x2boys · 21/09/2026 10:30

What are they then?
I get mixed up with currents ,raisens and Sultanas .

All grapes, just different kinds (and maybe dried in a different way)

mrswhiplington · 21/09/2026 10:33

NicNakNicola · 21/09/2026 10:04

I was an adult when I found out narwhals are real and not a mythical creature in the same category as fairies, mermaids and unicorns 😂

I was the same with wolverines.

Kokonimater · 21/09/2026 10:35

Thrownunderthebuz · 21/09/2026 03:17

Very low brow but only this weekend discovered that a UV light supper charges any glow in the dark item. It is plainly obvious now that the glow item absorbs UV.

Years of tuning lamps upside down to get stuff to glow better for the children and myself as a child solved with a £6 USB UV light.

Still can’t quite believe it 😳

Pardon?? B

User454545454546565 · 21/09/2026 10:37

Changeisstillpossible · 21/09/2026 09:13

That Arkansas isn't pronounced as it is written

This was a revelation to me as well. I still think ar-kan-zass (wrong) sounds way better.

SoupSoup · 21/09/2026 10:37

EvieBB · 21/09/2026 10:22

What? I always rinse. Are you not supposed to?

No. It washes off the fluoride that protects your teeth.

Phloosie · 21/09/2026 10:41

Bargarran · 21/09/2026 09:50

I was well into my 30s, maybe, before I realised West Berlin was surrounded by East Germany. How emasculating for the DDR to have half of one of your major city belonging to another country.

I knew the geography but, as a child, assumed that there was an underground tunnel between West Berlin and West Germany - I wasn’t clear if it was rail or road, but it seemed fairly obvious that it must exist or else Post-WW2 Germany made no sense.

I also thought the Iron Curtain was a physical structure along the lines of the Berlin Wall and the Great Wall of China, but bendier being made of chain linked metal.

farmlass · 21/09/2026 10:42

You are sort of right with Elliot Ness
He was one of the agents/cops in the film “The Untouchable’s” hunting down Al Capone .
I can now envisage Nessie swimming down the New York sewers .
I think it was a true story and a fantastic film with Sean Connery and Kevin Costner and Robert de Niro

DoraChance · 21/09/2026 10:42

JudgeJ · 21/09/2026 09:39

I recall drinig through an industrial area and seeing a huge sign saying TOILET, I only realised later that the I was an addition.

Not discovered as quite an adult but when I was about 16 my mother commented that I had the knife in my left hand when peeling an apple! We realised that I always use my left hand for some tasks when I am generally right-handed, it's called cross dominence.

I have this too, never realised there was a name for it. I write with my left hand, if I pick up a guitar I instinctively hold it the Paul McCartney way, but I would always use my right side for scissors, kicking a ball or chopping an onion. Holding a kitchen knife with my left hand feels wrong. That’s really interesting.

AlwaysExtraHot · 21/09/2026 10:43

GETTINGLIKEMYMOTHER · 21/09/2026 09:33

Not me, but I was shocked some years ago to find that dh, who has a degree and prof. qualifications, and attended a very academic boys’ school, had never heard of photosynthesis. The whole process on which life on earth depends, was completely new to him.

That I find quite mind-blowing. And I'm not a science mind at all.

Purplecatshopaholic · 21/09/2026 10:44

Twokittenchaos · 21/09/2026 07:04

Washington D.C isn’t in Washington state. Not quite as practical as some of the above but still a bit of a “who knew!” age 30-odd. Apparently most people.

No way! Mind blown

Datgal · 21/09/2026 10:44

FlorenceBlack · 21/09/2026 07:15

I didn’t know until a couple of years ago you could adjust seatbelts on cars. In my defence I learned to drive decades ago when they were set at fixed points so hadn’t ever noticed that newer cars had more sophisticated technology. I was chuntering to DH about being strangled by a seatbelt and why do all car manufacturers think we’re six foot tall? And he said well why don’t you move the thingy lower down…

Hilarious...I sort of knew you could. But just in the last few weeks, I figured this was the case in my car. Was sick of it digging in. And lo and behold.

Phloosie · 21/09/2026 10:49

I can only think about gravitational forces for so long, before I get a headache. I can still rattle off definitions and the mathematical derivations from physics classes, but I cannot quite grasp it at a level I’m comfortable with.

I read Leonardo da Vinvi’s paper on tides (basically slosh theory) and felt it made a lot more sense than magical invisible forces exerted by the moon. There are quite a lot of things that I’m supposed to believe as an intelligent adult, that are quite a bit dafter than the things I believed as a child.

SoupSoup · 21/09/2026 10:51

Isabella70 · 21/09/2026 10:32

All grapes, just different kinds (and maybe dried in a different way)

Yes, currants are dried red grapes of a specific variety called Black Corinth, traditionally grown in Greece — ‘currant’ is from the French term ‘raisins de Corinthe’. Sometimes called Zante currants in the US. Raisins and sultanas are both dried white grapes, but raisins are dried Muscatel grapes, and sultanas are from a couple of different varieties of white grapes, sometimes called sultanina grapes.

Confusingly, some countries/ cultures don’t distinguish between them at all, and just class them all as different types of raisins. In France, sultanas, currants and raisins are all under the category of types of ‘raisin sec’.

VenusThighTrap · 21/09/2026 10:53

Why did the chicken cross the road?
to get to the other side

I did not realise until someone pointed it out recently that other side = death.

Datgal · 21/09/2026 10:56

sherbetlemonade · 21/09/2026 10:01

But what are you supposed to do with all the froth?

This made me chuckle. I get a lot of 'froth' and it goes everywhere. So much so, my boyfriend always comments on it and it makes him laugh. He doesn't really get much. And it's not like I'm using tons of paste either. I don't get it 😂