Spotting Assumptions and Bias

Introduction

Imagine someone says to you: "We should buy Sam a football for his birthday — he'll love it!" This sounds reasonable, but it hides an assumption: the speaker is assuming that Sam likes football. What if Sam prefers reading, or swimming, or chess? The speaker has assumed something without checking whether it's true.

Assumptions are hidden beliefs that people take for granted without stating them or proving them. Bias is when someone's personal views, experiences, or interests unfairly influence their writing or arguments. Both assumptions and bias can weaken an argument — and the FSCE 11+ exam will test your ability to spot them.

What Are Assumptions?

An assumption is something that a speaker or writer believes to be true without saying so directly and without providing evidence for it.

Every argument rests on assumptions. Sometimes those assumptions are reasonable. Sometimes they are not. The skill is in spotting them and deciding whether they are justified.

Example:

• Statement: "If we build a new playground, the children will be happier."
• Hidden assumption: Children want a new playground. (What if they'd prefer a library or a nature garden?)
• Another hidden assumption: A new playground will make children happy. (What if the old one was fine?)

graph TD
    A["Statement or Argument"] --> B["What is being SAID?"]
    A --> C["What is being ASSUMED?"]
    B --> D["The explicit claim and evidence"]
    C --> E["Hidden beliefs the argument depends on"]
    E --> F{"Is the assumption reasonable?"}
    F -->|Yes| G["The argument may still be strong"]
    F -->|No| H["The argument is weakened"]
    style D fill:#e3f2fd
    style E fill:#fff3e0
    style G fill:#e8f5e9
    style H fill:#fce4ec

How to Find Hidden Assumptions

To find hidden assumptions, ask yourself:

1. "What must be true for this argument to work?" — If you can think of something that the argument depends on but doesn't state, that's an assumption.
2. "Is there a gap between the evidence and the conclusion?" — The assumption is often the missing link.
3. "Would everyone agree with this?" — If not, it might be an assumption rather than a proven fact.

What Is Bias?

Bias means that someone's personal interests, experiences, or views unfairly influence how they present information. A biased piece of writing doesn't give a fair or balanced picture — it pushes one point of view.

Important: Having an opinion is not the same as being biased. Everyone has opinions. Bias is when someone presents their opinion as though it's the only reasonable view, or when they leave out important information that goes against their opinion.

Types of Bias

Type	What It Means	Example
Selection bias	Only choosing evidence that supports your view	A sweet shop owner saying "Sweets make you happy!" but not mentioning tooth decay
Language bias	Using emotional or loaded words to influence the reader	Describing one side as "brave freedom fighters" and the other as "dangerous rebels"
Source bias	The person giving information has a personal reason to say it	A games console company saying "Video games improve children's intelligence"
Omission bias	Leaving out important information	A school advertising "100% pass rate" without saying they excluded some students from the exam

How to Spot Bias

Look for these signs:

1. One-sided arguments — Is only one point of view presented?
2. Emotional language — Are words designed to make you feel something rather than think?
3. Missing information — Is anything important left out?
4. Who is the author? — Do they have a personal reason to present a particular view?
5. Loaded words — Words like "obviously," "clearly," "everyone knows" try to stop you questioning the argument.

Worked Examples

Worked Example 1: Spotting Assumptions

Statement: "We should cancel the school trip to the museum and go to a theme park instead. The children will have much more fun."

Hidden assumptions:

1. The purpose of the school trip is to have fun. (Maybe it's meant to be educational?)
2. All children enjoy theme parks more than museums. (Some children might prefer museums.)
3. Fun is more important than learning on a school trip. (Many people would disagree.)
4. A theme park visit would be the same cost and equally practical. (It might be much more expensive.)

Notice how identifying the assumptions reveals weaknesses in the argument.

Worked Example 2: Spotting Bias in an Advertisement

Advertisement: "SuperBright Toothpaste is the ONLY toothpaste recommended by dentists! Switch to SuperBright today and you'll NEVER have a cavity again! Don't trust other brands — they use inferior ingredients that could DAMAGE your teeth."