What does a single counterexample prove?
One genuine counterexample can disprove an absolute claim. If someone says every room in a building has a window, finding one windowless room is enough to reject that statement. It does not prove most rooms lack windows, so the corrected conclusion must stay within what the evidence actually shows.
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Match the evidence to the claim's strength
The words all, always and never create strong claims. A statement that all rooms have windows is contradicted by one verified room without a window.
That same observation does not settle a weaker claim such as most rooms have windows. Establishing that would require information about the wider set of rooms.
A counterexample challenges the universal rule, not every related statement.
This distinction keeps corrections precise. After finding an exception, the original claim might become most rooms have windows or all rooms on the first floor have windows, if further evidence supports that wording. Replacing an exaggerated claim with an equally exaggerated opposite simply creates a new reasoning error.