Module 4 · Thinking skills · Practical technique

Spotting your assumptions

Most conclusions rest on something we never checked. Finding it changes the conclusion.

6 min read · Level: Beginner · Free — no account needed to read

The idea

Most conclusions rest on things we never checked. “He didn’t reply, so he’s annoyed with me” assumes he saw the message, had time, and would normally reply fast. Any of those could be wrong, and the conclusion falls with them.

Assumptions aren’t bad — you couldn’t get through a day without them. The trouble comes when a painful or important conclusion rests on an assumption you are treating as a fact.

A useful habit is to ask, when a conclusion stings: “What would have to be true for this to be right?” Listing the hidden steps often reveals one that is shaky — and once you see it, you can check it, or at least hold the conclusion more loosely.

Why it works

Many hard feelings come from conclusions built on unexamined assumptions. Finding them is one of the quickest ways to take the heat out of a situation — and to avoid acting on a mistake.

A real example

The situation

Rehana’s manager asks to “have a quick chat tomorrow”. She spends the evening convinced she is about to be criticised.

What happened

She asks what would have to be true: that quick chats are always bad news, that she has done something wrong, that her manager is unhappy. She realises she has no evidence for any of these. The next day the chat is about a new project.

The takeaway

Spotting the assumption didn’t change the meeting — it changed her evening.

Use this when you are…

• a conclusion is making you anxious or upset
• you are about to act on something you haven’t checked
• someone else’s behaviour is confusing you

Common mistakes

• Treating assumptions as facts because they feel certain.
• Trying to live without assumptions. The aim is to check the important ones.
• Only questioning assumptions that lead to conclusions you dislike.

What the evidence says

Practical technique: A widely used, low-risk practice drawn from established approaches, but not tested much on its own. Its value is mostly that it is simple and harmless to try.

Examining the assumptions behind conclusions is a core part of cognitive therapy and of critical-thinking teaching. It is a practical skill rather than a technique tested on its own.

Where this comes from: Cognitive behavioural therapy (CBT) research; Evidence-based medicine and critical appraisal.

Fields that study this: Clinical psychology.

Try it now: What would have to be true?

1. Write down a conclusion that has been bothering you.
2. List three things that would have to be true for it to be right.
3. Mark which ones you actually know, and which ones you have assumed.

Practise with a guided technique

• Fact or story? — (3–5 min · Practical evidence)
• Best, worst, most likely — (5 min · Practical evidence)

Questions to think about

• Which assumption about yourself do you most often treat as fact?
• What is one assumption you could check this week with a simple question?

Try this today

When you catch a strong conclusion today, ask: “what would have to be true for this to be right?”

Afterwards, ask yourself

Which assumption turned out to be shaky, and what changed when you saw it?

Words in this lesson

• Thinking trap — A common pattern a stressed mind falls into, such as all-or-nothing thinking, mind-reading or fortune-telling. Useful to notice in your own thinking — never a label for someone else.