Skepticism

# "I don't believe in stuff that sounds so illogical!"

Yesterday, while walking back from lunch with a friend of mine, he mentioned that he was related to Edgar Allen Poe. I decided to make a biology-nerd joke and said “so am I, he and I share a common ancestor”. My friend didn’t get it, and I started explaining to him how if it weren’t for cousin marriage which can be done much more coherently by Richard Dawkins in this extract from River Out of Eden:

You have two parents, four grandparents, eight great grandparents, and so on. With every generation, the number of ancestors doubles. Go back g generations and the number of ancestors is 2 multiplied by itself g times: 2 to the power g. Except that, without leaving our armchair, we can quickly see that it cannot be so. To convince ourselves of this we only have to go back a little way, say to the time of Jesus, almost exactly 2000 years ago. If we conservatively assume four generations per century (i.e. people breed, on average, at the age of 25) 2000 years amounts to a mere 80 generations. The real figure is probably more than this (until recent times, many women bred extremely young) but this is only an armchair calculation and the point is made almost regardless of such details. Two multiplied by itself 80 times is a formidable number, a 1 followed by 24 noughts, a trillion American trillions. You had a million million million million ancestors who were contemporaries of Jesus, and so did I! But the total population of the world at that time was a fraction of a negligible fraction of the number of ancestors we have just calculated.

Obviously we have gone wrong somewhere, but where? We did the calculation right. The only thing we got wrong was our assumption about doubling up in every generation. In effect, we forgot that cousins marry. I assumed that we each have eight great grandparents. But any child of a first cousin marriage has only six great grandparents, because the cousins’ shared grandparents are in two separate ways great grandparents to the children. So what? you may say. People occasionally marry their cousins (Charles Darwin’s wife Emma Wedgwood was his first cousin) but surely it doesn’t happen often enough to make a difference? Yes it does, because ‘cousin’ for our purposes includes second cousins, fifth cousins, sixteenth cousins … That makes all the difference because, when you count cousins as distant as that, every marriage is a marriage between cousins. You sometimes hear people boasting of being a distant cousin of the Queen but it is rather pompous of them because we are all distant cousins of the Queen and of everybody else, in more different ways than can ever be traced. The only thing that is special about royalty and aristocrats is that they can do the tracing explicitly. As the fourteenth Earl of Home said when taunted with the title by his political opponent: “I suppose Mr Wilson, when you come to think of it, is the fourteenth Mr Wilson.”

The upshot of all this is that we are much closer cousins of each other than we normally realise, and we have many fewer ancestors than simple calculations suggest.

“So, technically we’re all distant cousins” I finished after struggling for words so that I could sound coherent enough so that it would make sense.

But I doubt that he would have accepted that fact no matter how succinctly I explained it. It’s not at all that the kid in question is unintelligent.

“What? No, we can’t all be cousins. That’s too stupid.”

Questioning him further on why he thought it was stupid, I found that despite his claim that he was not deeply religious, he nonetheless refused to believe that life on Earth had evolved, nor that the Earth was 4.6 billion years old, believing that it was 50,000 years old (which is the equivalent of believing that a Star Destroyer is about 2 centimeters long) and that a god really did create an Adam and an Eve (and somehow we still aren’t all cousins with common ancestors).

Wait, so… how did he decide this was right?

“I’m not an extremist religious person, and I’m not an extremist scientists… like you are,” he told me.

First of all, I had to ask him when was the last time a proponent of evolution blew up a building because some other scientist believed in Genesis. Next, I had to ask him why he accepted certain parts of science like the existence of cells (I mean, somebody as complex as me made up of trillions of bags of jelly that I can’t see? PAH! That’s too reductionist… can bags of jelly write blog posts? Hahahahaha…).

“Because it sounds so illogical,” and I had to wonder how an invisible “dude” (as he referred to what he thought god was) creating Adam and Eve 53,000 years ago sounded any more logical.

On the other hand, this sounds pretty logical to me.

Not that that’s relevant in any way. What sounds logical has nothing to do with it. What’s logical has little to do with what the conclusion of the logical proof. Logical means you have reasons for why you got to the conclusion that you got to.

Recall the Monty Python clip. Although their reasoning was full of non-sequiturs (conclusion does not follow from premisses), however, they still had a line of reasoning to get to the conclusion that the woman was a witch. They were poor reasons… but at least they had them. The kid who thinks the Earth is 53,000 years old doesn’t even have a fallacy to back him up.

Reasoning combined with evidence has led us to some of the strangest revelations. I mean, seriously… The Earth isn’t the centre of the universe? But everything looks like it’s revolving around me! That doesn’t sound logical…

And yet it is. We have proof. We can observe the way the heavens move slightly more carefully.

I have one more thing to add.

I find it ironic that so many people accuse science of being closed-minded, not open to new ideas, and lacking in strangeness and wonder… and yet you have people who dismiss ideas like common ancestry out of hand because they’re strange, not caring for evidence.

We’re told that with faith all things are possible. Science doesn’t have a bias against any ideas, although I will concede that I can imagine scenarios where something could exist which science can’t prove the existence of (but in most of these scenarios it’s because these things have no impact on the physical world and thus no impact on us), as long as you have evidence to back yourself up.

I am often told about the power faith has to make all things possible, but with science all things are possible, but even better, it seeks truth in this wild universe of possibilities we could never dream of by asking for evidence.

There is a quote from Hamlet that is often quoted at scientists to tell them that their worldview is narrow for not believing in the supernatural, but I feel it should be quoted at all who deny evolution.

Horatio:

O day and night, but this is wondrous strange!

Hamlet:

And therefore as a stranger give it welcome.

There are more things in heaven and earth, Horatio,

Than are dreamt of in your philosophy.

And I end with one more quote, this time from the equally eloquent Carl Sagan…

Somewhere, something incredible is waiting to be known.

Not that that’s relevant in any way. What sounds logical has nothing to do with it. What’s logical has little to do with what the conclusion of the logical proof. Logical means you have reasons for why you got to the conclusion that you got to.

Recall the Monty Python clip. Although their reasoning was full of non-sequiturs (conclusion does not follow from premisses), however, they still had a line of reasoning to get to the conclusion that the woman was a witch. They were poor reasons… but at least they had them. The kid who thinks the Earth is 53,000 years old doesn’t even have a fallacy to back him up.

Reasoning combined with evidence has led us to some of the strangest revelations. I mean, seriously… The Earth isn’t the centre of the universe? But everything looks like it’s revolving around me! That doesn’t sound logical…

And yet it is. We have proof. We can observe the way the heavens move slightly more carefully.

I have one more thing to add.

I find it ironic that so many people accuse science of being closed-minded, not open to new ideas, and lacking in strangeness and wonder… and yet you have people who dismiss ideas like common ancestry out of hand because they’re strange, not caring for evidence.

We’re told that with faith all things are possible. Science doesn’t have a bias against any ideas, although I will concede that I can imagine scenarios where something could exist which science can’t prove the existence of (but in most of these scenarios it’s because these things have no impact on the physical world and thus no impact on us), as long as you have evidence to back yourself up.

I am often told about the power faith has to make all things possible, but with science all things are possible, but even better, it seeks truth in this wild universe of possibilities we could never dream of by asking for evidence.

There is a quote from Hamlet that is often quoted at scientists to tell them that their worldview is narrow for not believing in the supernatural, but I feel it should be quoted at all who deny evolution.

Horatio:

O day and night, but this is wondrous strange!

Hamlet:

And therefore as a stranger give it welcome.

There are more things in heaven and earth, Horatio,

Than are dreamt of in your philosophy.

And I end with one more quote, this time from the equally eloquent Carl Sagan…

Somewhere, something incredible is waiting to be known.

1. I do so love Hamlet ðŸ™‚ You might want to fix the reduplication issue above, by the way.

Nice article, as always.

2. I had a roommate in college who refused to accept the existence of black holes. Now, his complaint wasn’t with how we detect black holes, but rather that black holes simply didn’t exist at all. For some reason he couldn’t grasp the idea that an object could have a gravitational field so strong that no light could escape from it. Incredibly dense white dwarfs were fine, and he accepted the existence of gravitational lensing… but nope, no black holes. After awhile I just gave up on trying to explain it to him. /shrug

Anyway, well said. And that quote from Hamlet always reminds me of one of my all time favorite quotes, usually attributed to J.B.S. Haldane…

“Not only is the universe stranger than we imagine, it is stranger than we can imagine”

3. One of my favorite quotes is by Neils Bohr, which he made about Quantum Theory but which I think applies to science as a whole. The gist of it is, “If you aren’t blown away, you haven’t understood a thing.”

I think people who blow off science as destroying our sense of wonder fall into this category of just not understand WHAT exactly it is that science has figured out. The more you learn, the MORE fascinating the universe becomes… but I know you already know this. ðŸ™‚

4. Here’s a more relevant Sagan quote that you can send him:

“Science imposes, in exchange for its manifold gifts, a certain onerous burden. We are enjoined also to consider ourselves scientifically , to surmount as best we can our own hopes and wishes and beliefs, to view ourselves as we really are.

We know that in looking deep within ourselves, we may challenge notions that give us great comfort in the face of the many terrors of the world. In a life short and uncertain, in a time when – precisely because of the success of medicine – people die mainly from medically incurable disease, it seems heartless to deprive them of the consolation of superstition when science cannot cure their anguish.

But we cannot have science in bits and pieces, applying it where we feel safe and ignoring it where we feel threatened. That way lies hypocrisy, self-deception, and a dangerously constrained future.”