Professor of Philosophy at the University of Bristol.

My name's Samir Okasha, I'm Professor of Philosophy of Science

in the Philosophy Department, University of Bristol.

The topic we're going to discuss concerns the status of ethics,

in particular, objective versus subjective views of ethics.

According to the subjective view,

there are no facts of the matter about ethical questions.

For example, if someone says "euthanasia is right"

and someone else says "euthanasia is wrong",

ultimately, that's a matter of subjective taste, not scientific fact.

So if that's the case,

why do people think they're having disagreements

that can be resolved by argument?

After all, if I say "chocolate ice cream's nice"

and you say "No, it isn't",

there's nothing more to be discussed

because we acknowledge that each of us is expressing our taste

and there's no further fact of the matter.

One of the strongest arguments for the subjective view,

which in part responds to that objection,

is the fact that different communities around the world at different times

have held widely divergent ethical views.

Some people have thought, for example, it's OK to perform honour killing

of young girls who get pregnant out of wedlock.

Other communities find that to be an abhorrent thing to do.

And you can think of many examples like that.

A natural response to that

that the subjective view gives is to say

"That's because there's no fact of the matter in the first place".

It's a bit like a preference for chocolate ice cream over strawberry.

There are also widespread divergences

in beliefs among different cultures

about matters that we're not tempted to regard as not factual.

For example, different cultures have disagreed

about whether or not the Earth is round

as opposed to flat

or about the origins of the universe of the nature of matter.

The difference with the ethical case is that, in those scientific cases,

there's a reasonably agreed-upon method

for establishing which answer is correct,

even if it's hard sometimes.

In the ethical case, there don't seem to be any comparable methods

to decide whether, for example, euthanasia is or is not morally wrong.

I take your point that we can't do experiments

to find out the answer to ethical questions, however,

we do have procedures and methods.

One of those methods is the method of rational persuasion which people use

in attempting to bring others round to their moral point of view.

So if we think of the Abolitionist Movement

or the campaign for the emancipation of women,

in both cases, a large part of their methods

were that rational persuasion of other people through argument,

so how do you explain what's going on in that process

from a subjectivist point of view?

It's certainly true that, from a subjective point of view,

it's difficult to account for the idea

that we've made moral progress, for example.

We all tend to believe that we have made moral progress,

we've moved from times when slavery was dominant

to its abolition, say, over a period of a few hundred years -

and that seems to be progress.

But a subjectivist will say that it doesn't follow

that we've learnt the truth of some factual thing about the world

like slavery is wrong, where we used to think slavery was OK.

But a subjectivist will try to account for our sense of moral progress

without appealing to the idea

that it involved apprehending the truth

about objective moral facts.

Yeah, that's interesting. I'm not yet persuaded

that we have a reason to deny

that there are ethical truths.