8. Welcome to the solar system

This post marks the end of Part I of Essential Thinking for Philosophy. If you’ve been following from the start, you will have by now had a pretty rigorous introduction to the techniques of critical thinking. However, if you are a philosophy major, you need to start applying those skills to particular philosophical texts.

That’s precisely what we’ll be doing in Part II – Analysing Philosophical texts. However, to help you make the transition, in this last post of Part I, we will look at a fairly straightforward contemporary argument that concerns an empirical rather than philosophical matter (though that’s not to say it does not have philosophical consequences!). Nonetheless, in this text you will have the chance to practice the skills we’ve been rehearsing over the last fifteen posts or so and to prepare you for the challenges of Part II – Analysing Philosophical texts. The questions at the end of this text are precisely the same questions that you should ask yourself after reading any philosophical paper.

Enjoy! 🙂

Exercise 8
Read the text and try to answer the questions that follow.

Space is enormous. The average distance between stars out there is over 30 million million kilometres. Even at speeds approaching those of light, these are fantastically challenging distances for any travelling individual. Of course, it is possible that alien beings travel billions of miles to amuse themselves frightening some poor guy in a pickup truck on a lonely road in Arizona, but it does seem unlikely.

Still, statistically the probability that there are other thinking beings out there is good. In the 1960s, Frank Drake worked out a famous equation designed to calculate the chances of advanced life existing elsewhere in the cosmos. Under Drake’s equation, you divide the number of stars in a portion of the universe by the number of stars that are likely to have planetary systems; divide that by the number of planetary systems that could theoretically support life; divide that by the number on which life, having arisen, advances to a state of intelligence; and so on. At each such division, the number shrinks colossally, yet the number of advanced civilizations, just in our own Galaxy, always works out to be somewhere in the millions.

Unfortunately, space being spacious, the average distance between any two of these civilisations is reckoned to be at least two hundred light years. Figure that one light year is the distance traveled in one year by a pulse of light, and that light travels at 299,792 kilometers per second, then one light-year is, give or take a klick or two, about 9.46 trillion (9.46 x 1012) kilometers. A jetliner traveling at a speed of 800 kilometers per hour would need to fly for 1.34 million years in order to travel one light-year. Multiply that by 200 and we’re talking about a distance that is so far beyond us as to be, well, just beyond us.

So even if we are not really alone, in all practical terms we are. Carl Sagan calculated the number of probable planets in the universe at as many as ten billion trillion – a number vastly beyond imagining. But what is equally beyond imagining is the amount of space through which they are scattered. ‘If we were randomly inserted into the universe,’ Sagan wrote, ‘the chances that you would be on or near a planet would be less than a billion trillion trillion (less than 1 x 1033).’

a. What is the author’s main claim in this article?

b. What are the main premises of his argument?

c. What type of argument is it?

d. Is the argument convincing (i.e., do you believe it)?
Give reasons for your answer.

This excerpt is (C) copyright Bill Bryson and has been adapted for non-commercial, educational purposes from his ‘A Short History of Nearly Everything‘ – a book nearly every educated person should read. 🙂

When you are ready, check out the answer key here, or continue on to Part II

Follow me on Twitter or get the RSS feed to find out when the next post goes up.

  1. interesting text, can we discuss our answers

  2. Great blog, I really appreciate your work.

  3. Well done! Thanks for sharing!
    Wendy C. Hamblet

  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: