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Why can an inductive conclusion be likely without being certain?

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Marble bust of Aristotle with a beard and draped robe, showing detailed facial features and wavy hair, set against a dark background. — Applied logic Aristotle, marble portrait bust, Roman copy (2nd century bce) of a Greek original (c. 325 bce); in the Museo Nazionale Romano, Rome.

In the context of applied logic, an inductive conclusion is considered likely rather than certain because it is an ampliative inference, meaning it provides new information that is not strictly contained within the premises.1

Unlike deductive logic, where valid inferences guarantee that a conclusion must be true if the premises are true, inductive reasoning only guarantees that the conclusion is probable. Because inductive inferences move from observed instances to unobserved ones—or from the past to the future—it is always at least conceivable that the conclusion could be mistaken.21

For example, one might hear piano music and infer that someone is playing a piano; however, this is not certain, as the sound could be produced by an electronic synthesizer. This inherent uncertainty arises because inductive conclusions rely on the assumption that the future will resemble the past or that nature is uniform, an assumption that cannot be rationally established as a certainty. Consequently, while good inductive inferences provide a high degree of probability, they lack the absolute, truth-preserving necessity found in deductive systems.231