Logical Reasoning
Counter-example
A single case that shows a general statement is false.
| English | Counter-example |
|---|---|
| Bahasa Melayu | Contoh penyangkal |
| 中文 | 反例 |
How it is used
The statement "the product of two prime numbers is always odd" is false. A counter-example is 2 × 3 = 6, which is even.
This single case is enough to disprove the general claim.
Where it shows up in SPM
Counter-example is the disproving tool in Form 4 Logical Reasoning. Paper 1 may ask which value is a counter-example to a claim.
Paper 2 asks you to decide whether a general statement is true and, if not, to give a counter-example that shows it is false.
Don't confuse it with
Open the chapter: Logical Reasoning →
Frequently asked questions
How many counter-examples do I need?
Just one. To disprove "every number greater than 2 is prime", the value 4 is a counter-example because 4 = 2 × 2 is not prime.
A single valid case is enough; you do not need to list several.
Can a counter-example prove a statement true?
No. A counter-example can only show a statement is false.
To argue a general statement is true you need a proper reason that covers every case, not examples; finding examples that fit never proves no exception exists.