are moral assertions connected with the world of facts?"
Unlike many ancient philosophical problems, this one has, paradoxically,
been made both more urgent and less tractable by the gradual triumph
of scientific rationality. Indeed, the prevailing modern attitude towards
it is a sort of dogmatic despair: you cant get an ought
from an is, therefore morality must be outside the domain of reason.
Having fallen for that non-sequitur, one has only two options: either
to embrace unreason, or to try living without ever making a moral judgement.
In either case, one becomes a menace to oneself and everyone else.
On the tape of the bin Laden dinner party, a participant states his
belief that during the September 11 attack, Americans were afraid that
a coup détat was under way. Worldwide, tens of millions
of people believe that the Israeli secret service carried out the attack.
These are factual misconceptions, yet they bear the imprint of moral
wrongness just as clearly as a fossil bears the imprint of life. This
illustrates an important strand in the fabric of reality: although factual
and moral assertions are logically independent (one cannot deduce
either from the other), factual and moral explanations are not.
There is an explanatory link between ought and is, and this provides
one of the ways in which reason can indeed address moral issues.
Jacob Bronowski pointed out that a commitment to discovering scientific
truth entails a commitment to certain values, such as tolerance, integrity,
and openness to ideas and to change. But theres more to it than
that. Not only scientific discovery, but scientific understanding itself
can depend on ones moral stance. Just look at the difficulty that
creationists have in understanding what the theory of evolution says.
Look at the prevalence of conspiracy theories among the supporters of
bad causes, and how such people are systematically blind to rational
argument about the facts of the matter. And, conversely, look at Galileo,
whose factual truth-seeking forced him to question the Churchs
Why does this happen? We should not be surprised at least, no
more surprised than we are that, say, scientific and mathematical
explanations are connected. The truth has structural unity as well as
logical consistency, and I guess that no true explanation is entirely
disconnected from any other. In particular, in order to understand the
moral landscape in terms of a given set of values, one needs to understand
some facts as being a certain way too, and vice versa. Moreover, I think
it is a general principle that morally right values are connected in
this way with true factual theories, and morally wrong values with false
What sort of principle is this? Though it refers to morality, at root
it is epistemological. It is about the structure of true explanations,
and about the circumstances under which knowledge can or cannot grow.
This, in turn, makes it ultimately a physical fact but that is
Deutsch, a physicist, is a member of the Centre for Quantum
Computation at the Clarendon Laboratory, Oxford University, and author
of The Fabric of Reality.