"There's a monster under the slide!" "Grandma is coming today." "My friend has a hundred cats." Children say all sorts of things with total confidence. A gentle "How do you know?" invites them to think about where an idea came from, and whether it is something they saw, something they heard or something they guessed.
Learning to look for evidence is a thinking habit that lasts for life. It helps with school, with friendships, and later with everything children read and hear online.
Why ask "How do you know?"
- It separates ideas from facts. Children start to notice that believing something is not the same as knowing it.
- It builds reasons. Explaining "how I know" is the first step to explaining "why I think so".
- It protects them later. Children who ask "how do they know?" are less likely to believe everything they hear.
- It works both ways. Children can ask you too, and should.
Seeing, hearing, guessing
Help your child sort how they know something into three kinds:
| How I know | Example: "It's raining" |
|---|---|
| I saw it myself | "I can see raindrops on the window." |
| Someone told me | "Dad said it's raining." |
| I worked it out or guessed | "The sky is very dark, so I think it will rain." |
All three are useful. Seeing is usually strongest, but eyes can be fooled. What someone tells us depends on who it is and how they know. Guesses can be good or bad depending on the clues behind them.
How to ask kindly
The same words can sound curious or suspicious. Some tips:
- Use a curious voice. "Ooh, how do you know?" rather than "Prove it."
- Ask about good news too. Not only when you doubt your child.
- Accept "I don't know". It's an honest answer and worth praising.
- Answer the question yourself. "How do I know dinner is ready? I can smell it and the timer rang."
- Don't use it to win arguments. The goal is thinking, not catching your child out.
Check it together
When a claim can be checked, check it together:
- Go and look. "You think the cat is in the garden? Let's look out of the window."
- Ask who told you. "Who said the park is closed? How might they know?"
- Look for more than one clue. "Wet umbrellas and wet shoes: two clues that it's raining."
- Change your mind happily. "Ah, the cat is on the sofa. Good thing we checked!"
Everyday games
- How do I know? Say something you know and let your child guess how: "Someone is at the door." (I heard the bell.)
- Mystery bag. Put an object in a bag. Your child feels it and says what they think it is and which clues tell them.
- Weather check. In the morning, guess the weather from clues out of the window, then check later.
- Seen, heard or guessed? Read short sentences aloud and sort them: "I saw a fox." "My friend said there was a fox." "There are footprints, so maybe a fox came."
Ideas by age
Ages are rough guides; every child is different.
- Around 4–5: "Did you see it or did someone tell you?" in everyday moments, the mystery bag.
- Around 6–7: sorting seen, heard and guessed, looking for two clues, checking together.
- Around 8 and up: asking how others know (news, adverts, rumours at school), saying how sure they are, changing their mind when new evidence appears.
In Dologi, the Logic topic has "Who lives here?" puzzles: children read clue cards and work out which robot lives in a house. Every answer has to come from the clues, not from a guess.
In short
- "How do you know?" helps children separate believing from knowing.
- Sort knowledge into seeing, hearing and guessing; all three are useful but different.
- Ask with curiosity, ask about good news too, and answer the question yourself.
- Check claims together and show that changing your mind is a good thing.