Overfitting a puzzle means building an unnecessarily elaborate rule around the examples you can see. The rule may reproduce those examples while offering little reason to trust the proposed next step.
A short sequence does not prove a unique rule
For 2, 4, 6, a simple continuation is 8 under add two. You could also invent a rule that follows those first three values and then switches to 100. Both fit the displayed terms, but the second adds an unsupported exception.
Reasoning questions normally ask for the intended simple relationship within their context and options. They do not establish that no mathematically constructed alternative is possible.
Prefer explanation over rescue
Suppose your proposed rule works for three transitions but fails on the fourth. Adding a special case just for the failure should make you cautious. First ask whether another compact rule explains every transition without exceptions.
For example, splitting odd and even positions may explain an apparently irregular sequence more cleanly than a long list of unrelated additions.
Use an unused example as a check
Form a candidate rule from part of the information, then test it on a complete row or transition you have not yet used. This is not a statistical validation study, but it is a useful reasoning habit: the rule must do more than restate the clue that inspired it.
If it fails, revise the hypothesis rather than ignoring the inconvenient example.
Compare candidates explicitly
- How many operations does each rule require?
- Does each account for every provided example?
- Does it preserve the relevant visual features?
- Does the question's wording restrict the allowed rule?
Know when uncertainty is reasonable
If two simple rules genuinely fit all the evidence and point to different available answers, the item may be ambiguous. In practice, acknowledge that ambiguity instead of inventing confidence. The goal is disciplined reasoning, including knowing what the information does and does not determine.