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Philosophy, Science and Religion: Science and Philosophy

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The University of Edinburgh

Philosophy, Science and Religion: Science and Philosophy

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Philosophy, Science and Religion mark three of the most fundamental modes of thinking about the world and our place in it. Are these modes incompatible? Put another way: is the intellectually responsible thing to do to ‘pick sides’ and identify with one of these approaches at the exclusion of others? Or, are they complementary or mutually supportive? As is typical of questions of such magnitude, the devil is in the details. For example, it is important to work out what is really distinctive about each of these ways of inquiring about the world. In order to gain some clarity here, we’ll be investigating what some of the current leading thinkers in philosophy, science and religion are actually doing. This course, entitled ‘Science and Philosophy’, is the first of three related courses in our Philosophy, Science and Religion Online series. The first launch is now closed to enrolments. We will launch a new version of the course in July 2018. The course will address four themes each presented by guest lecturers: 1. Are Science and Religion in conflict? (Professor Michael Murray, Franklin & Marshall) 2. Neuroscience and Free Will (Professor Al Mele, Florida State) 3. Creationism and Evolutionary Biology--Science or Pseudo-science? (Dr. Mark Harris and Dr. David de Pomerai, University of Edinburgh) 4. Do Scientific claims constitute absolute truths? (Professor Martin Kusch, University of Vienna) The second and third courses in the Philosophy, Science and Religion series are ‘Philosophy and Religion’ and ‘Religion and Science’. They may be taken in any order and completing all three courses will give you a broader understanding of this fascinating topic. Look for: • Philosophy, Science and Religion II: Philosophy and Religion • Philosophy, Science and Religion III: Religion and Science Check out our trailer to hear more: https://youtu.be/OifqTI5VKek You can also follow us on Twitter at https://twitter.com/EdiPhilOnline and you can follow the hashtag #psrmooc

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Neuroscience and Free Will

In this module Professor Al Mele presents experiments that purport to show that there is no such thing as free will. He then presents three criticisms of this interpretation of the evidence.

Introduction10:11

Study 2 and 34:35

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Dr J Adam Carter
Researcher
Epistemology - Philosphy
Dr Orestis Palermos
Research Explorer
School of Philosophy
Dr Mark Harris
Senior Lecturer in Science and Religion
School of Divinity
Professor Duncan Pritchard
Professor of Philosophy
University of Edinburgh

I move to problem two.

Here is a second problem that all three studies have in common.

And it's a problem about the point of no return.

So, I have given talks about this sort of thing and

sometimes I do persuade people of my first point.

That we don't have good evidence that decision or

intentions are made at the early times and

that they may well be made around 200 milliseconds before muscle motion.

Sometimes I hear in response to that.

Well okay, so maybe that's right but even so,

the point of no return is hit at these early times.

Now, the point of no return is a point such that once a process hits it, it's

just going to roll on to completion unless there's some kind of special interference.

So their claim then is that once the brain gets to that point,

in the decision making process, the point of no return has been hit.

But that would mean that the point of no return has been hit, before there's

any consciousness of a decision, and before there's any real decision.

And the thought is, well if the point of no return is hit back there,

before conscious deciding, then free will really isn't involved in the production

of the decision or the action that executes the decision.

That's the claim, so what we want to know now is,

is the point of no return hit that early?

So, look at the purple box in the diagram and

one thing we'd want to know then is whether we have good evidence that,

thinking about Levitt's study in particular, that in that box,

the point of no return has been hit.

Now how would we get evidence of that?

We'd want to be able to look and see whether we ever get

a curve that has that shape in that part of the box but

is not followed by muscle motion.

So do you ever get a curve that looks like that but no muscle motion,

that's what we need to look for.

Now it turns out that given Libet's method in the main study,

there's no way to look for that.

And why is that?

Because when you do EEG studies, you need to do something called back averaging.

And so your computer needs to get a signal

telling it to make a record of the preceding second or so of brain activity.

And what Libet used as a signal to the computer to make a record of that

activity was muscle motion.

So it was only when there was muscle motion

that you got these charts that you could read.

But given that muscle motion is the trigger, you're precluded from looking for

cases in which you get a curve that looks like that in the purple box but

no muscle motion, and let me just read you a quotation.

Sometimes people think this can't be right but it is.

Here's the quotation from Libet and his method.

In the absence of the muscle's electrical signal when being activated, there

was no trigger to initiate the computers recording of any preceding brain activity.

So in other words you can't look for what you want to look for

in order to see whether the point of no return has been hit that early.

Also you can look for independent evidence of when the point of no return is hit.

Now my book Effective Intentions was published in 2009.

In one study I suggested, in that book,

was a stop signal study, and it was in connection with the point of no return.

So, if you want to know when the point of no return is hit in a process of

the kinds we're talking about.

One way to get evidence about it is to issue stop signals to people and

move them closer to or further from the time you're interested in.

And see whether there's time for

people to stop a process in response to the stop signal.

And the simple sort of study I suggested was this.

You could tell subjects to flex a wrist

when the spot or hand hit the 9 o' clock point on the clock.

Unless the clock face changed color from white to red.

So at the start of the study, it's going to be white, and you can tell them,

okay, now you can flex whenever you want, unless

the clock face changes color to red, and then if it turns red, don't do it.

Otherwise, do it.

And what I predicted back then,

because average stop signal reaction time is about 200 milliseconds is that if you

gave them 200 milliseconds or a little more, they'd be able to stop.

So just picture a clock, picture the 9 o'clock point, imagine

putting a stop signal really close to that 9 o'clock point like a 100 milliseconds.

That probably wouldn't do it, people are probably going to flex when it hits nine.

But if you move it back to a little more than 200 milliseconds my prediction was,

people will have time to stop.

Now why is that relevant?

Well, if they had time to stop,

then they haven't really hit the point of no return in this process earlier.

It can be stopped by an external signal.

And if it can be stopped by an external signal, why not be stopped by an internal

signal too, just telling yourself, no, don't do it.

Wait for the next urge or whatever.

So recently there is a study done by Schultze-Kraft and colleagues.

It was published in 2016.

It's way more sophisticated than the one I

sort of made up as an example back in 2009.

And in this study they use actual EEG readings

to make predictions about when people will click when they'll move,

and they designed a stop signal study that is sensitive to real time EEG.

So they're predicting on the basis of the EEG when people will move and

then they're using stop signals based on those predictions.

Moving the signal around closer and farther from the predicted time.

And the signal they used was a red light.

So, the instruction was like driving a car, so

this is foot motion this time.

The instructions was, after you get the green light you

can press that button on the floor whenever you want but

don't do it if the light changes to red.

And what they discovered with their red stop signal is

that if there was no motion within 200 milliseconds of

the red light showing up, in general there wasn't any motion.

So that would be evidence that 200 milliseconds or so is enough

to stop this process, which again, is evidence that the point of

no return is not hit earlier than 200 milliseconds before muscle motion.

Now recall that the claim here that I'm countering

is that even though decisions maybe are not made at those early times,

the point of no return is hit at the early times.

At minus 550 milliseconds, at minus 800 milliseconds,

at minus 7 to 10 seconds before muscle motion.

And what we have here is evidence that the point of no return,

is not hit until about 200 milliseconds before muscle motion and

that as it happens is right around W time, the time of first awareness of

the decision or intention to do the thing in question.

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