Scientist: All other things being equal, the intensity of heat increases as the distance from the heat source decreases  Knowing this, <b> most people conclude that the Earth's seasons are caused by the Earth's changing distance from the sun  </b> In other words, winter occurs when the Earth is far from the sun, and summer occurs when the earth is close to the sun  However, <b> we know that as North America experiences summer, South America experiences winter, even though the difference in the continents' distance to the sun is negligible </b>
Ttherefore, the earth's changing distance from the sun does not cause the seasons
The first describes a common belief that follows logically from the statement before it; the second is factual information that the scientist deems to be irrelevant to her argument.