Quote by Douglas Adams
If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family anatidae on our hands.
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Summary
This quote suggests that when something or someone exhibits all the characteristics and actions typically associated with a particular thing or group, it is reasonable to assume that they are part of that category. In this case, it implies that if an entity appears and behaves like a duck, it is likely to be a member of the duck family. The quote encourages us to consider and acknowledge the obvious traits and attributes instead of denying or ignoring them.