Method of Difference

Adam and Bill order Chinese food. They both have Kung Pao beef and Szechuan bean curd, but Bill doesn’t try the chicken lo mein. An hour later, Adam becomes violently ill, with vomiting and stomach cramps. These symptoms resemble those of food poisoning.

Adam: beef, bean curd, chicken Event

Bill: beef, bean curd No Event

Method of Difference

Method of Agreement

Alex and Jenny go to a cookout. They both eat BBQ ribs. Jenny has a side of cole slaw. Alex has a side of potato salad and apple pie for dessert. Later, they both end up with severe headaches. What is the cause of these symptoms?

Alex: ribs, potato salad, pie Event

Jenny: beef, cole slaw Event

Method of Agreement

Joint Method of Agreement & Difference

Ben, Colleen, and Jeana all had headaches. Ben took aspirin with caffeinated coffee. Colleen took ibuprofen with caffeinated coffee. Jeana took acetaminophen with decaffeinated coffee.

Ben and Colleen’s headaches went away, but Jeana’s did not. What could have resulted in Ben and Colleen’s headache relief?

Ben: aspirin, caffeinated coffee Event

Colleen: ibuprofen, caffeinated coffee Event

Jeana: acetaminophen, decaffeinated coffee No Event

Joint Method of Agreement & Difference

The Flashlight

You have two battery-operated, bulb-type flashlights.  The green one works; the blue one doesn't.  You switch batteries.  The green flashlight no longer works, but the blue one does. 

Why is this? 

Which of Mill’s Methods explains this situation?

Green:B1, L1 Event

Blue: B2, L2 No Event

Blue: B1, L2 Event

Method of Joint Agreement & Difference

Method of Concomitant Variation

When I run regularly, my right knee hurts. When I don’t go running, my right knee doesn’t hurt.

Method of Concomitant Variation

S1: When people intake more than 30 mg. of saturated fat, the diastolic number of their blood pressure increases above normal (80).

S2: When people intake less than 30 mg. of saturated fat, the diastolic number of the diastolic number of their blood pressure is closer to normal (80).

Pasteur

Explain why this test was convincing.

Which of Mill’s methods does Pasteur’s experiment employ?

Pasteur

Exposed: Broth1, A1 Event

Sealed: Broth1, A2 No Event

Method of Difference

Getting Women in the Mood

♀ Rats: C, ♂1 Event

♀ Rats: No C, ♂1 No Event

Method of Difference

Getting Women in the Mood

• Which of Mill’s Methods explains how this experiment was set up?

Getting Women in the Mood

Could also conduct the experiment using the Method of Agreement, Joint Agreement & Difference, and Concomitant Variation

Getting Women in the Mood

• ♀ Rats: Caffeine, Romantic Flick, Sexy ♂ Rats Event

• ♀ Rats: Caffeine, Disco, Homely ♂ Rats Event

Method of Agreement

• ♀ Rats: Caffeine, Romantic Flick, Sexy ♂ Rats Event

• ♀ Rats: Caffeine, Disco, Homely ♂ Rats Event

• ♀ Rats: Popcorn, Romantic Flick, Sexy ♂ Rats No Event

Joint Method of Agreement & Difference

Getting Women in the Mood

Getting Women in the Mood

Increase in the amount of caffeine given to ♀ rats increases the likelihood that they’ll find the ♂ rats appealing

Decrease in the amount of caffeine given to ♀ rats decreases the likelihood that they’ll find the ♂ rats appealing

Concomitant Variation