The Logic of 'If A, Then B'

The term 'if A, then B' is regularly mentioned on this blog, and a couple of you have asked me to explain this in a bit more detail.


Let's take an example:

Say, aloe vera.

If (A)
an analysis of aloe vera shows it contains components that can be beneficial to skin and even help encourage healing,
then (B)
it seems logical to assume aloe vera will effectively help speed up the skin's healing process.

It might be true, but until documented, it is 'only' an assumption.

And Assume, We Do

In aloe vera's case, the 'if A, then B' logic has prevailed for decades. But science is about finding and documenting facts. And to date, science isn't on board with all of aloe vera's assumed properties.

The Natural Medicine Journal writes this about aloe vera: 

"Despite its widespread popularity, scientific evidence on the aloe vera gel remains sparse."

In the same article, they conclude:
"...the use of aloe vera gel or its components for the treatment of a variety of conditions and diseases needs further clinical evidence through well-designed studies with defined aloe extracts and matching placebo controls." (link to article)

Medline Plus writes this about aloe vera:
"Some chemicals in aloe gel seem to be able to increase circulation in the tiny blood vessels in the skin, as well as kill bacteria. Together, these effects suggest that aloe gel might be effective in speeding wound healing. But it’s too early to come to that conclusion. Evidence is contradictory. One study suggests that aloe gel may actually delay wound healing." (link to page)

We Choose To Believe We Think We Know

The 'if A, then B' line of logic is widespread in the cosmetics industry, but is just as popular with manufacturers of supplements and vitamins.

One example; the company Life Extension has even made this line of logic their mantra, making and marketing their products based on their own 'if A, then B' assumptions.

It can be very tempting to perceive the 'if A, then B' line of logic as evidential. It's also understandably easy to buy into it as such. I mean, who wouldn't want a magic pill or cream that removes wrinkles, takes off unwanted pounds overnight, or repairs broken bones in record time because (some) science (almost) says so?

Exactly. I'll take two, please!

In Conclusion, a Little Quiz

So, let's try using the 'if A, then B' line of logic with a little quiz. Please read the statement below, then choose the correct answer:

If (A) 
Lise has experienced 80% positive results with hair growth using caffeine on a test group of 5 people,
then (B) 
80% of everyone else using the same method and product will experience the same positive results.

Is the above statement:
A: A conclusion based on anecdotal evidence
B: Hard core documented scientific evidence because if Lise tested it, it must be true for the rest of the world

We all know the answer is A, but personally, I'd love it if the correct answer could be B.

More About the Science of Aloe Vera

Aloe Vera Gel Research
Aloe Vera shows a moisturizing effect in cosmetic formulations in this study
Medline Plus: About aloe vera