Progymnasmata: Confirmation & Refutation Chapter 3 pp. 116 #2.

Debatable question from history:

Confirmation
Assertion to be confirmed:
There is life on at least one other planet.
Encomium (Panegyric), discourse of praise:
"NASA remains a leading force in scientific research and in stimulating public interest in aerospace exploration, as well as science and technology in general."
Exposition of the Situation:
"There is also a strong possibility of planets outside of our solar system having the conditions necessary for life. Our galaxy, the Milky Way, contains at least 200 billion (200,000,000,000) stars, and recent observations with very powerful telescopes suggests that many of the stars in the night sky have planets orbiting them. There is a famous equation called Drake's Equation that tries to calculate how many stars contain orbiting planets that have conditions suitable for the development of life. The equation suggests that life forms are very likely to exist on planets in our galaxy or any of the billions of other galaxies in the Universe. Scientists are still working hard to observe earth-like planets around other stars, and to understand the conditions under which life formed and evolved on the ancient Earth." - Brian W. Stewar
"Understanding planetary habitability and the relationship between the occurrence of life and the evolution of planets is a primary organizing theme of NASA's Solar System Exploration Program."
Certainty:
"In the process of photosynthesis, plants convert energy from the sun into chemical energy in the form of glucose, or sugar. The chlorophyll in plants absorbs more blue and red light from sunlight, and less green light. Chlorophyll is green, because it reflects green light more than blue and red light."
Credibility:
"Since its inception in 1958, NASA has accomplished many great scientific and technological feats in air and space."
Possibility:
"NASA scientists believe they have found a way to predict the color of plants on planets in other solar systems."
Consistency:
"No one knows" - David Morrison
Propriety:
According to the reliable source Nancy Kiang, detecting the color of plants on other planets is possible. "Kiang and her colleagues calculated what the stellar light would look like at the surface of Earth-like planets whose atmospheric chemistry is consistent with the different types of stars they orbit. By looking at the changes in that light through different atmospheres, researchers identified colors that would be most favorable for photosynthesis on other planets. This new research narrows the range of colors that scientists would expect to see when photosynthesis is occurring on extrasolar planets."
Convenience:
"Mars, Titan, Europa, and other promising objects"
Refutation
False assertion to be refuted:
There is life on at least one other planets.
Exposition of the Situation:
Same as above
Uncertainty:
"Thre is no direct evidence today of life on any planet beyond Earth. The search for life beyond Earth is one of the major goals of astrobiology." - David Morrison
Incredibility:
"...only on Earth does the whole complicated mix come together in a way that encourages life"
Impossibility:
"In order for life (in the form that is most familiar to us) to evolve on a planet, scientists believe that the planet must be warm enough to contain at least some liquid water, but not so hot that all of the water turns to vapor, as appears to be the case on the planet Venus." - Brian W. Stewar
Lack of Consistency:
"In order for life (in the form that is most familiar to us) to evolve on a planet, scientists believe that the planet must be warm enough to contain at least some liquid water, but not so hot that all of the water turns to vapor... It must also contain certain important elements, like carbon and nitrogen, that are necessary to build living cells, and the environment must be calm enough that life has time to develop - the planets in some star systems may be hit so frequently by giant meteorites (causing all the surface water to boil or vaporize) that life never has a chance to form there." - Brian W. Stewar
Impropriety:
"There is no direct evidence today of life on any planet beyond Earth." - David Morrison
Inconvenience:
"little is presently known about habitable environments within our Solar System"