Stargazing Guy

– Carl Sagan, The Demon-Haunted World: Science as a Candle in the Dark

The first ten of Sagan’s twenty most common and perilous pitfalls — many of which are rooted in our chronic discomfort with ambiguity — are available here – one and two (blog 1 of 11), three and four (blog 2 of 11), five and six (blog 3 of 11), seven and eight (blog 4 of 11), nine and ten (blog 5 of 11).

The eleventh and twelfth of these pitfalls is covered below, with Sagan’s examples.

11. non sequitur — Latin for “It doesn’t follow” (e.g., Our nation will prevail because God is great. But nearly every nation pretends this to be true; the German formulation was “Gott mit uns”). Often those falling into the non sequitur fallacy have simply failed to recognize alternative possibilities;

12. post hoc, ergo propter hoc — Latin for “It happened after, so it was caused by” (e.g., Jaime Cardinal Sin, Archbishop of Manila: “I know of … a 26-year-old who looks 60 because she takes [contraceptive] pills.” Or: Before women got the vote, there were no nuclear weapons);

Here are some other examples:

11. non sequitur:

a) Exercising regularly improves physical health.
b) Alice exercises regularly.
c) Therefore, Alice is more physically healthy than Bob.

OR

a) Cars are bad for the environment.
b) Bicycles and cars are used for transportation.
c) Therefore, bicycles are bad for the environment

12. post hoc, ergo propter hoc – “Every time that rooster crows, the sun comes up. That rooster must be very powerful and important!”

AND

“Nearly all heroin addicts used marijuana before they tried heroin. Clearly marijuana use leads to heroin addiction.”

PS: I love coffee. BuyMeACoffee, leave a message with a date and time and we can share it, remotely, at the same time, and think about the Cosmos.

In the meantime, take care of yourself and if you can, someone else, too, because as Adam Smith said, “we naturally desire not only to be loved but to be lovely”.

Remember, hope lives here.

Contact Stargazing Guy for any copyright-related requests or queries @ stargazer1@stargazingguy.co.uk