Welcome to Defenders, the teaching class of Dr. William Lane Craig. Today, the Doctrine of Man,

Part 15. For more information and resources from Dr. Craig, go to reasonable faith.org.

Welcome to Defenders class. Coming to you from my home office during this time of

quarantine, I almost feel as though we should rename the class Defenders in Exile.

But we're all doing well. Jan and I are well in the midst of this time of sequestration.

Though the COVID-19 virus has touched the reasonable faith family,

one of our staff members in Oklahoma who is involved in this live stream of the Defender's

class, came down with the virus, and has been feeling pretty crummy. But he's soldiering through

and is actually helping with the live stream this morning as we go out.

I received a question on Facebook concerning last week's lesson that I thought worth addressing this morning before we move to the lesson today.

Someone said, why do you associate absolute brain size with increased cognitive capacity or intelligence?

Aren't there other mammals, for example, elephants that have much larger brains than human beings,

and yet they're not more intelligent than human beings.

Well, the answer is that in hominins, in particular, brain size is positively correlated

with increased cognitive capacity and intelligence.

With respect to other mammals who have larger brains than human beings like whales or elephants,

what is crucial here is to also consider not simply the absolute size, but what's called

the encephalization quotient, which is a sort of ratio between brain size and body mass.

And when you calculate that, you find that the encephalization quotient for whales and elephants

is very small, whereas for human beings, it's somewhere around seven.

So when you look at the so-called EQ, as well as the absolute brain size, this confirms

that the increased brain size in hominence is positively correlated with an increase in cognitive capacity and intelligence.

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