1.3
Deductive reasoning is a type of logic that uses general principles to make specific predictions or conclusions.
It is the opposite of inductive reasoning, where general principles are inferred from specific observations.
Both types of reasoning are used to generate and test hypotheses.
For example, a scientist observes that butterflies are attracted to red flowers, but not yellow ones.
Using inductive reasoning, the scientist forms a hypothesis that butterflies choose flowers based on petal color.
Deductive reasoning begins when the scientist asks what should happen if this idea is correct.
If butterflies truly chose flowers based on color, then changing the petal color should change the butterflies' attraction to them.
However, changing other features, like scent or petal shape, should not make a difference if color is the main reason.
The scientist tests these predictions by changing one factor at a time and observing how the butterflies respond.
When the results match the prediction, the idea about color gains support.
In this way, inductive reasoning helps scientists form ideas, and deductive reasoning helps them test those ideas to expand scientific understanding.
演繹的推論、すなわち演繹は、仮説に基づく科学で用いられる論理の一種です。演繹的推論では、思考の流れは帰納的推論とは逆の方向に進みます。一般的な原理や法則を用いて、具体的な結果を予測します。科学者は、これらの一般的な原理から、その一般原理が正しい限り妥当であり続ける具体的な結果を予測することができます…
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