Reference no: EM133584317

Problem: For each English passage, reconstruct the intended argument and write it out in standard form. Next, say whether you think the argument is valid or invalid. Provide an informal proof or counterexample to show that your evaluation is correct. Everyone now alive had two parents each of whom in turn had two parents. It follows that in our grandparents' day, there were four times as many people as there are today. If our satellite photographs show the remains of abandoned towns and cities on the surface of Mars, then there was once intelligent life on that planet. But our satellite photographs show no sign of abandoned towns or cities on the surface of the planet. We can only conclude that there has never been intelligent life on Mars. Either men are superior to women or women are superior to men. But men are not superior to women. So, it follows that women are superior to men.