目前探究教學著重歸納或假設一演譯的觀點，而忽略理論選擇也是科學探究的重要 一環。本研究依據地理界與地質界對泥火山水來源的爭議做爲背景，提供理論選擇式的探 究，以研究高中學生如何進行理論選擇。首先由泥火山相關論文及學生晤談，來發展水來 源理論選擇問卷，以便學生經由對證據或理由的評斷來進行水來源探究，並對競爭理論進 行選擇，最後進行問卷的量化分析及個案晤談。 從因素分析結果發現：影響學生理論選擇的因素有「信念」因素（包括相信權威、直 覺、及同儕）和「推論」因素（包括素模推論、溯因推論、假設預測、事實推論、及類比 推論）。不同的學生對影響其作判斷的因素有不同的偏好，而根據其理論選擇情形可分爲 四類：1.素模型，偏好素模推論；2.邏輯型，偏好邏輯推論（包括溯因推論、假設預測、 及事實推論）；3.混合型，將二競爭理論混合形成新理論，偏好相信權威與直覺；4.改變 型，前後測選擇不同理論，偏好素模及邏輯推論。 綜合量化分析和晤談結果發現：權威、直覺及素模推論在學生做理論選擇時扮演重要 角色，尤其資訊越不足時，學生越不用邏輯推論來選擇，其選擇也越固著。而對證據的詮 釋只是用來鞏固自己原來的選擇，甚至相同的證據也可能用來支持相對立的理論。

At present, teaching science as inquiry in high school typically is dominated by inductive or hypothetico-deductive views of science, and theory-choice, an essential element of scientific inquiry for scientists commonly is ignored. Based on the debate between geographic and geological communities on the origin of water in mud erupted from on-land mud-volcano at Wushanding in southern Taiwan, this study attempted to provide a theory-choice-based inquiry for students to explore how high school students make their theory choice between two competing theories. The research involved a survey, an inquiry of the origin of mud volcano water, and interviews. At first, a questionnaire comprised of a set of rationales was constructed as a survey tool and used to help students inquiring about the mud-volcano water’s origin and making a choice between two competition theories. Then a factors analysis was conducted to find out the factors affecting students’ theory-choice. The results showed that students made theory-choice according to subjective beliefs (i.e., belief in authority, peer, and intuition) and objective inferences (i.e., naïve inference, abduction inference, hypothetico-prediction, fact-based inference, and analogy inference). The influential strength of each factor depended on the individual student’s preference. According to their choices, students may be categorized into four groups: ( ) Naïve, who preferred naïve inference, ( ) Logical, who preferred logical inference (i.e. abduction inference, hypothetico-prediction, and fact-based inference), ( ) Mixed, who mixed two competition theories to form a new theory and preferred belief in authority and intuition, and ( ) Changed, who made different choices in pre and post-test and preferred naïve and logical inference. This study also found that authority and intuition played main roles in students’ theorychoice as well as naïve inference, especially when lack of sufficient information for reference. Many students tended to use naïve inference to make choice rather than logical inference. They chose it just because they believed it is true. Students who preferred making theory choice depending on their belief, their choice more likely stood firm and was hard to change. They even tended to recognize all of rationales as supports of their choice although the rationale maybe supports the alternate.