Look at the following examples and decide which exhibit a pattern which is deductively valid and which do not.
8.5.1 If the world’s climate is getting warmer, we should fi nd that some of the ice at both the North and the South Pole is melting at an unusually high rate. If the ice is melting, we should see its effect in the raising of the level of the sea. The world’s climate is getting warmer so we should fi nd evidence that the sea level is rising. (Don’t confuse with Questions appendix, passage 3.)
8.5.2 If people who claim to have been abducted by aliens really have been abducted, then we would need to take reports of UFO sightings very seriously. However, such claims are very unlikely to be true. Therefore, we do not need to take reports of UFO sightings seriously. (Cf. Questions appendix, passage 7)
8.5.3 A group of reputable European scientists has reported that studies they have conducted do not demonstrate that there is a significant risk of lung cancer from passive smoking. But this analysis was commissioned by the tobacco industry. So findings of the analysis are likely to be incorrect. (Cf. Questions appendix, passage 11)
8.5.4 If it was true that the benefits to animals from toxicity tests on animals outweigh the suffering of the animals involved in the tests, these tests might be justified. Unfortunately for those who countenance such tests, the benefit to animals cannot be established, so toxicity testing on animals is not justifi ed. (Cf. Questions appendix, passage 16)