Evaluating evidence on ACT Science: deciding whether a new finding supports, weakens, or is neutral to a viewpoint by checking it against that view's specific claim and reasoning.

What this topic is asking

The most demanding Conflicting Viewpoints questions give you a new piece of evidence and ask whether it supports, weakens, or is neutral to a particular view. This is pure Evaluation reasoning: you must hold the view's specific claim in mind and ask whether the new finding makes that claim more or less likely. The trick is to always check the evidence against the right view's claim, not against the phenomenon in general.

Anchor on the specific claim

Every evaluation question starts by recalling the claim of the view named. Evidence is judged relative to a claim, so you must know exactly what that claim asserts before you can say whether the finding helps or hurts. This is why tracking each view's claim in a phrase (tracking each viewpoint's claims) pays off here: the claim is the yardstick against which you measure the new evidence.

Support: does the evidence match a prediction?

Evidence supports a view when it is what that view would predict. Ask: "If this view were correct, would we expect to see this finding?" If yes, the finding strengthens the view.

• A comet-impact claim predicts a large impact crater; finding one of the right age supports it.
• A soot-camouflage claim predicts darker moths survive better where bark is darker; data showing exactly that supports it.

The mental move is claim then prediction then match: state the claim, ask what it predicts, check whether the new finding fits.

Weaken: does the evidence remove what the claim needs?

Evidence weakens a view when it contradicts the claim or takes away a mechanism the claim relies on. Ask: "Does this view depend on something the finding shows is absent or false?"

• A volcanic-cause claim depends on large-scale volcanism; finding no such activity weakens it.
• A claim that a chemical wash triggers germination is weakened by a finding that seeds germinate just as well without any washing.

Removing the claim's required mechanism is the clearest way evidence weakens a view.

Neutral and the rival-view trap

Two subtleties the ACT tests:

• Neutral evidence. A finding that bears on neither claim leaves both unchanged. Not every new fact is relevant; if it does not touch a claim's prediction or mechanism, its effect is none.
• Supporting one view does not disprove the other. Strengthening Scientist 1 makes Scientist 1 more likely, but it does not by itself prove Scientist 2 wrong, unless the two claims are strict opposites. Be wary of answers that leap from "supports one" to "refutes the other."

How the ACT phrases these

• Support: "Which finding would strengthen Scientist 1's hypothesis?"
• Weaken: "Which finding would most challenge Scientist 2's explanation?"
• Effect: "What effect would this result have on the two views?"

For each, anchor on the specific claim, then decide whether the finding matches a prediction (support), removes a needed mechanism (weaken), or touches neither (neutral).

Try this

Q1. A view claims a disease is spread by mosquitoes. A new study finds the disease appears only where those mosquitoes live. Does this support or weaken the view, and why? [2 points]

• Cue. It supports the view, because the claim predicts the disease should track the mosquitoes' range, and the finding matches that prediction.

Q2. Explain why evidence that supports Scientist 1 does not automatically prove Scientist 2 wrong. [2 points]

• Cue. Strengthening one claim makes it more likely but does not by itself remove the other's mechanism or contradict its claim, unless the two claims are strict opposites; support and refutation are separate judgements.