Phil 145: Portfolio Examples

The following four examples are taken from past portfolios. Note that each clearly states the source, example, and analysis.

Portfolio 1:



“With British Columbia recently deciding to let it’s universities set their own tuition rates, it will only be a matter of time before Ontario University presidents join together and ask for the same power.”



Premise 1: British Columbia let it’s universities set their own tuition rates.

Implicit Premise 2: If Universities from B.C. do something, then Ontario Universities will do the same.

Conclusion: Given time, Ontario universities will behave like B.C. universities.

SLIPPERY SLOPE: The author provides a sequence of events which does not hold from one end to another.  The reader is led to believe that University governments think uniformly and their behavior can be predicted by observing the behavior of others.  One cannot assume the implicit premise 2.



IMPRINT, University of Waterloo student newspaper.  Vol. 24 No. 28. p.4 “Deregulation requires consolidation” by Jon Willing. Feb. 22nd 2002. 



“Fermi realized that any civilization with a modest amount of rocket technology and an immodest amount of imperial incentive could rapidly colonize the entire galaxy.  Within ten million years, every star system could be brought under the wing of empire.

So what Fermi immediately realized was that the aliens have had more than enough time to pepper the Galaxy with their presense.  But looking around, he didn’t see any clear indication that they’re out and about.  This prompted Fermi to ask what was (to him) an obvious question : ‘Where is Everybody?’

This sounds a bit silly at first.  The fact that aliens don’t seem to be walking our planet apparently implies that there are no extraterestrials anywhere in the vast tracts of the galaxy.”



Premise 1: Capable civilizations could fully colonize the galaxy in ten million years.

Implicit Premise 2: Our galaxy is much much older than that.

Conclusion 1: Aliens have had more than enough time to colonize the galaxy.

Premise 3: Aliens don’t walk around on Earth.

Conclusion 2: Aliens do not exist.

IGNORANCE: We have not seen aliens yet, even though they have had more than enough time to colonize the entire galaxy.  Therefore, they do not exist.  This is a classical example of “If A has not been proven, then A does not exist”.



SETI: search for Life.  “Our galaxy should be teeming with Civilization, But Where are They?”  By Beth Shostak, Astronomer, Project Phoenix.  October 25, 2001. shostak_paradox_011024.html

Thanks to Adam Stanley for the previous two examples.

Portfolio 2:

Alternative Medicine

Quote: The San Diego International Center (SDC) claims to have the capabilities of reversing cancer and autoimmune diseases by using non-toxic vaccines and therapies that stimulate that body's immune system. The "Anti-Mycoplasma Autologous Vaccine (Myc-Vacc)", the therapy they use, supposedly "stimulates the immune system to recognize cancer-causing agents and to begin to fight back." One case is cited in extensive detail of Myc-Vacc being used on a cancer patient, and that patient's cancer remitting.

Analysis: Although it is very likely that there is something wrong with the supposed therapy being offered, it is difficult (not being medically trained) to identify the medical shortcomings of the therapy. What can be pointed out, though, is that the author of the article uses Post Hoc Ergo Propter Hoc to try to prove the case in favour of the therapy. The patient in the case, "Charles", underwent the Myc-Vacc therapy and then, in undera a year, was completely cancer-free. Even if we assume that the case of Charles is true, it is anecdotal and syas nothing abut the efficacy of the therapy in general. One cannot confidently claim that because a person's cancer remitted after a specific treatment that the treatment was the cause of the remission. More importantly, we can't know if the therapy will work for others based on one anecdotal example. People might also be drawn to this therapy because there is a plausible explanation for it -- that it aids the immune system.



Quote: Abraham Lincoln is said to have had a premonition of his own death in a dream. He related this to a friend, Ward Hill Lamont:

"About ten days ago, I retired very late. I soon began to dream. There seemed to be a death-like stillness about me. Then I heard subdued sobs, as if a number of people were weeping. I thought I left my bed and wandered downstairs. There the silence was broken by the same pitiful sobbing, but the mourners were invisible. I went from room to room. No living person was in sight, but the same mournful sounds met me as I passed alone. I was puzzled and alarmed. Determined to find the cause of a state of things so mysterious and shocking, I kept on until I arrived at the East Room. Before me was a catafalque on which rested a corpse wrapped in funeral vestments. Around it were stationed soldiers who were acting as guards; and there was a throng or people, some gazing mournfully upon the corpse, whose face was covered, others weeping pitifully. "Who is dead in the White House?" I demanded of one of the soldiers. "The president," was his answer. "He was killed by an assassin.""

Analysis: It's not unlikely that lincoln would have dreamed about something like his own death. There were a lot of Americans at the time who did not like Lincoln, and he had in fact received many death threats. With death threats on his mind, it is not surprising that he dreamt about his death. What makes that story so impressive is that only a short time later, he was assassinated. We cannot, however, say that Lincoln was gifted with ESP or precognition, because there are better explanations. It was a likely coincidence that he would dream about his own death and then later die. Also, he did not dream the specific sequence of events that occurred. Also consider that premonitions are 'one-sided events' -- that is, this dream of death would never have become famous had he died many years later (it would have been forgotten).

Source: Microsoft Encarta Encyclopedia, 2001, Abraham Lincoln. And,

Thanks to Jonathan Boyd for the previous two examples.