Linguistics is a science and can only be understood as a discipline by
treating it as such.
The first step, therefore, is to be clear about what science is, and that is
what this lecture sets out to explain.
The word science comes from Latin scientia, 'knowledge', and in current usage
refers to knowledge of the natural world, that is, of the world and the cosmos in
which we live.
More specifically, science consists of a large collection of best guesses or
hypotheses about the natural world which have been tested by observation of
the world and, for the time being, are regarded as valid explanations of why the
world and the universe are as they are and how they will develop in future.
Science makes no claim to absolute truth, however: if further observation
contradicts existing hypotheses, these are either appropriately emended or
replaced with ones consistent with observation.
The discussion is in two main parts: the first part outlines the historical
development of science, and the second examines its nature, that is, the
philosophy of how science should be pursued.
1. The history of science
From the time that historical records begin to appear, and for a long time
before that, humans have tried to understand the environment in which
they lived partly as a matter of curiosity and partly as a way of controlling
that environment.
This attempt at understanding has historically taken two main forms:
mythology and empirical science.
1. The history of science
1.1 Mythology
The earliest known attempts to
understand the natural world took the
form of mythology,
that is, a system of narratives in which
aspects of nature were personified as
gods and goddesses, and the
interaction of natural processes as well
as human interactions with these
processes were conceptualized as
personal interactions among deities and
humans.
1. The history of science
1.1 Mythology
Religion was and is the ritual whereby humans interact with the gods in the
hope of influencing them to provide, for example, good harvests or success in
war.
Mythology and religion have remained influential in human understanding of
the natural world from prehistory to the present day, as the widespread
contemporary allegiance to Christianity and Islam as well as to smaller
religions attests.
1. The history of science
1.2 Empirical science
Empirical knowledge is knowledge gained by observation, and empirical
science is therefore knowledge of the natural world gained by observing it.
This differs fundamentally from mythology, which explains the natural world by
positing a range of unobservable deities and interactions among them and
with humans.
1. The history of science
1.2 Empirical science
1.2.1 Empirical science in prehistory
As a species, humans are late arrivals in the history of the world. On current
estimates, the world is about four and a half billion years old, but creatures
that we would recognize as humans rather than some kind of ape have only
existed since about 500,000 BC.
Our species, homo sapiens, is more recent still, first appearing about 200,000
BC. This means that we have been here for about 0.0001% of the world's
existence.
1. The history of science
1.2 Empirical science
1.2.1 Empirical science in prehistory
For most of those 200,000 years humans were what archaeologists and
anthropologists call hunter-gatherers.
They lived in small groups, had a few primitive stone tools, and fed
themselves by foraging for edible plants and by hunting animals.
To avoid exhausting local resources these groups were frequently on the
move; there were no permanent settlements.
All of humanity was at the hunter-gatherer stage of development until about
10,000 BC, or about 12,000 years ago.
1. The history of science
1.2 Empirical science
1.2.1 Empirical science in prehistory
Apart from what can be inferred from occasional archaeological finds, we
have no direct knowledge about the thought-worlds of these early humans,
and certainly none about what kind of science they had, if any.
Some hunter-gatherer population groups have, however, survived into
relatively modern times --for example North American Indians, sub-Saharan
Africans, and Australian aboriginals until the 19th century-- and a very few,
such as the Amazonian Indians, have managed, just, to survive to the present.
From observation of such groups we can infer that the science of prehistoric
cultures at the hunter-gatherer stage of development was predominantly or
exclusively mythological.
1. The history of science
1.2 Empirical science
1.2.2 Empirical science in early historical times, c.10,000 - c.500 AD
The world's temperature is constantly changing, and there have been at least
five periods of severe cold when large parts of the earth's surface have been
covered by ice.
The last of these Ice Ages ended, in the sense that the vast majority of the
world's surface became largely ice-free, by about 10,000 BC.
1. The history of science
1.2 Empirical science
1.2.2 Empirical science in early historical times, c.10,000 - c.500 AD
At about that time things began to change in one particular part of the world
that we now call the Middle East, but was anciently known as Mesopotamia.
1. The history of science
1.2 Empirical science
1.2.2 Empirical science in early historical times, c.10,000 - c.500 AD
Here, from about
10,000 BC, wild
plants and cereals
began to be cultivated
and wild animals like
sheep and goats to be
domesticated.
This provided a more
predictable food
supply, and by about
5000 BC settlements
began to appear on
the banks of the rivers
Tigris and Euphrates
1. The history of science
1.2 Empirical science
1.2.2 Empirical science in early historical times, c.10,000 - c.500 AD
The Mesopotamian developments soon spread eastwards into present day
Pakistan and northern India and thence into China, and westwards around
the Mediterranean basin.
Egypt had its pharaohs and pyramids, Greece its acropolis and philosophical
schools.
About the year 0 the Roman Empire had come into being ,and controlled the
territories surrounding the Mediterranean as well as most of present-day
Europe.
1. The history of science
1.2 Empirical science
1.2.2 Empirical science in early historical times, c.10,000 - c.500 AD
A major development at this time was the invention of writing.
The implications of this invention for the development of human culture are
huge, and a later lecture examines them in detail.
For present purposes, though, its importance lies in the following two
observations.
• Firstly, it allows human history to be recorded for the first time; in this part of
the world at least, we move from prehistoric to historic times.
•And, secondly, it made the first developments in empirical science possible.
1. The history of science
1.2 Empirical science
1.2.2 Empirical science in early historical times, c.10,000 - c.500 AD
For example:
•Traditional knowledge about healing plants and curative procedures was
systematized and the earliest form of medicine.
•Observation of the heavens for purposes of timekeeping and navigation laid
the foundations for later astronomy.
•The need for measurement in the construction of cities and various other
forms of technology led to the earliest forms of mathematics. The Greeks, in
particular, made major advances in geometry.
•Greek philosophers from the 7th century BC onwards began to think about
how knowledge is acquired, and among other things systematized deductive
and inductive forms of reasoning, thereby laying the foundations of modern
philosophy.
1. The history of science
1.2 Empirical science
1.2.3 Empirical science in early historical times, c.500 - c.5500 AD
By about 500 AD the
cultural developments
outlined in the preceding
section had spread over an
extensive part of Eurasia,
from present-day Western
Europe to China
Scientific ideas continued to
develop across this
area, but to keep the
discussion within bounds
we will focus on Western
Europe in what follows.
1. The history of science
1.2 Empirical science
1.2.3 Empirical science in early historical times, c.500 - c.5500 AD
Between about 0 and 500 AD
Rome controlled an empire that
comprised the Mediterranean
Basin, north-western Europe,
and parts of the Middle East.
This Roman Empire was the
culmination of the cultural
development described in the
foregoing discussion, and
prospects were good.
Two factors delayed that
development for the best part of
the next 1500 years, however:
1. The history of science
1.2 Empirical science
1.2.3 Empirical science in early historical times, c.500 - c.5500 AD
Over the space of several
centuries, groups from northeastern Europe outside the
Empire began to attack and then
settle within its borders.
By 500 AD the Empire in the
West had been engulfed and
ceased to exist as a political
entity.
The kingdoms established by
these peoples are the foundation
on which present-day Western
European society is built.
1. The history of science
1.2 Empirical science
1.2.3 Empirical science in early historical times, c.500 - c.5500 AD
The problem was that these
settlers were at a much lower
level of cultural development
than that of the Roman Empire.
They were unable to
understand Roman institutions.
As a result these institutions
were severely damaged, and it
took many centuries for
Western European society to
recover the Roman level of
culture.
1. The history of science
1.2 Empirical science
1.2.3 Empirical science in early historical times, c.500 - c.5500 AD
Christianity, originally a small sect of
Judaism founded in the decades after
the death of Jesus Christ in 33 AD,
grew in popularity…
to the extent that, by the early fourth
century AD, it became the official
religion of the Empire.
After the end of the Empire it spread
into Western Europe and there became
ideologically dominant at least until
about 1500 AD.
This period between about 500 AD and
1500 AD is known as the Middle Ages.
1. The history of science
1.2 Empirical science
1.2.4 Empirical science in Western Europe c.1500 - present
The dominance of Christianity in Western Europe included a rigidly enforced
ideological orthodoxy: that humankind's place in the natural world was to be
understood in terms of Christian theology, that is, mythologically.
It was only with the advent of the cultural movement known as the Renaissance
between about 1300 and 1500 that this orthodoxy began to be questioned.
Intellectuals began once again to base their understanding of nature on
observation of it.
1. The history of science
1.2 Empirical science
1.2.4 Empirical science in Western Europe c.1500 - present
The medieval view of cosmology, for example, was
that the earth was at the centre of the universe
and surrounded by a succession of spheres.
This was questioned by astronomers like
Copernicus (1473–1543), Kepler (1571–1630),
and Galileo (1564–1642), who proposed that the
earth revolved around the sun.
Such developments were fiercely resisted by the
Christian ecclesiastical establishment.
Despite that opposition empirical science
developed rapidly and, in our own time, it offers a
highly-developed and ever-developing
understanding of the natural world.
1. The history of science
1.2 Empirical science
1.2.4 Empirical science in Western Europe c.1500 - present
Mythology remains hugely influential throughout the world, however, and is
frequently antagonistic towards empirical science.
2. The nature of science
In current Western society,
“science” seems to have a
special status.
If you can convince the right
people that the investigation
you’re doing is scientific, you get
benefits which are not given to
people who are not doing
‘scientific’ work.
This man just finished a threepart series on his (and others’)
work broadcast in prime-time on
the BBC (and in high definition).
2. The nature of science
Professor Brian Cox says he
can explain what’s going to
happen in the future, various
things that the stars will be
doing, etc.
The woman who sits in this
caravan in the Bigg Market
makes similar sorts of claims.
However, Angeline Lee is
unlikely to be given her own
show on the BBC anytime soon
(maybe Channel 5 though).
2. The nature of science
One of the reasons for this special treatment is that science appears to lead
to a special kind of knowledge – true, certain knowledge about the way the
world actually is.
When scientists make a claim like “sodium chloride dissolves in water” (on
the basis of appropriate evidence), it’s not a hope, or a belief. It has some
kind of different status.
Why is this? What’s special about the investigation that Professor Brian Cox
carries out? How is it different from Ms Angeline Lee’s investigation?
The philosophy of science tries to get to grips with questions like these,
questions like “What is science, really?” and “How is scientific work done?”.
2. The nature of science
One of the most important things that the philosophy of science tells us is that
many ‘ordinary’ or ‘common sense’ views about science aren’t right.
The ‘common sense’ version of science essentially says that it is based on
(1) observations (2) of the real world which (3) are built up into
generalizations.
It turns out that all three of these things require a lot more thought than it
might seem at first glance.
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
A core component of the ‘common sense’ view of science is that impartial,
unbiased, theory-free observation plays a crucial role.
Scientists don’t approach their subject with any preconceptions.
They simply make observations about what happens in the world and build
these observations up into theories that describe the way the world actually
is.
These observations then constitute the data that the scientific theory tries to
explain.
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
‘Pure’ observation
However, (visual) observations are not just
“there for the taking”. They’re not like camera
photos on a retina.
Depending on how you look at it, most
Westerners will ‘see’ two different staircases.
However, the culture of some African tribes
does not have the tradition of representing 3D
objects two-dimensionally, and they report
only seeing a bunch of lines.
Whose ‘observation’ is right if observation has
a cultural dimension? What’s the ‘data’ here?
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
Observation can also be dependent on beliefs
and expectations.
In a famous experiment, Bruner and Postman
(1949) asked subjects to identify a series of
playing cards.
However, some cards were made anomalous
For the normal cards, the identification was
almost always correct, but the anomalous cards
were, without hesitation or puzzlement,
consistently identified as a ‘normal’ card.
What’s going on here?
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
Observation also appears to be biologically
conditioned.
A dot is quickly flashed in one location and
then another. If you get the timing right,
subjects will report that they saw one dot which
moved from one position to the other.
Thus, it seems like the notion of ‘pure’
observation, the main way data is supposedly
gathered under the common-sense view of
science, is a problem.
At the very least, the question is a lot more
subtle than it might seem at first glance.
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
Observation is theory-dependent
Another important point to acknowledge is that there is no such thing as
theory-independent observation, and therefore no such thing as ‘pure’
data.
All observations, even the most basic ones, presuppose a theory of the
world and the object under observation.
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
First, what you choose to observe depends on your theory.
In conducting a scientific experiment to measure radio waves, a physicist won’t
make a note of the colour of his shirt or the time of day. Why not?
If science is engaged in ‘pure’ observation, free of any theoretical bias, then
this decision isn’t rational.
Why is this factor ignored as opposed to any other?
The reason is that the scientist’s theory of radio waves says that those factors
aren’t relevant – that they won’t affect the experiment.
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
And if these theories are wrong, then the observations need to be discounted.
In the late 1800’s, the German physicist Heinrich Hertz did some experiments to
measure the speed of radio waves and ran into a problem.
Electromagnetic theory said that the waves should travel at the speed of light, but
when he and others measured it, they got a different value.
It turned out that one thing Hertz wasn’t measuring was the size of the room,
because, like the colour of his shirt, his theory said that it wasn’t relevant.
However, what happened was the radio waves were bouncing off the walls in the
room and hitting the detector, so it turned out that an error in the (unexpressed,
implicit) background theory invalidated the observations.
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
A similar issue arose in early astronomy.
The Copernican view of the solar system predicts that the size of Venus should
change appreciably during the course of the year, but observers on Earth didn’t
notice any change.
However the observation “Venus does not change size during the year”
presupposes a theory which says that the size of small light sources can be
accurately gauged by the naked eye, and this isn’t true.
Modern optical theory explains why this is true and why observations with a
telescope will be more appropriate. (And these show that Venus does indeed
change size significantly.)
2. The nature of science
2.1 There’s no such thing as data: the problem of observation
So, it looks like we need to think a bit more carefully about what exactly
constitutes ‘data’.
‘Data’ is not just there sitting around. It requires interpretation, within the
context of a theory which is as explicit as possible.
2. The nature of science
2.2 Idealization: the problem of the ‘real’ world
The idea that science studies the real world is another core part of the ‘common
sense’ view of science.
However, this idea comes with an important set of qualifications.
Scientists frequently engage in ‘idealization’. That is, ironically, you need to ‘get
away’ from the real world in under to understand how it works.
2. The nature of science
2.2 Idealization: the problem of the ‘real’ world
In traditional core natural sciences, with their long tradition, this is understood
perfectly well.
A chemistry experiment does not consist of digging up rocks from your back
garden and mixing it with water from the tap.
It consists of mixing some a pure sample of some material (say sodium) and
mixing it with water which is pure H2O.
Even if nowhere on the actual Earth could you find a ‘pure’ sample of sodium
or a ‘pure’ sample of H2O.
2. The nature of science
2.2 Idealization: the problem of the ‘real’ world
But if science is about studying the world, it seems like this shouldn’t be
legitimate.
How can you claim to be studying the world when your experiments contain
‘made up’, ‘unreal’ material that you’ve manufactured in a lab, rather than
what’s out there in the world?
However, when it comes to chemistry, this is never thought to be a
problem.
This is because everyone understands that the real world is complicated,
and full of interfering factors.
If you were to attempt to engage with the world in all its complexity, your
investigation would never progress. You’d never get anywhere.
2. The nature of science
2.2 Idealization: the problem of the ‘real’ world
What you need to do is try to make the problem simpler.
You try to factor out as many interfering factors as you can to try to get to the
underlying basic truth about the world.
Water that you get out of a tap contains all kinds of stuff – H2O, plus chlorine, plus
[insert favourite conspiracy theory here].
If you put sodium into the water and it starts sparking, is that due to the H2O, or
the chlorine, or the mind-control drugs?
If you dig up a random rock, dump it in pure H2O and the liquid turns blue, which
one of the 80 gajillion things that are in a random rock was the cause?
You have no way of knowing.
2. The nature of science
2.2 Idealization: the problem of the ‘real’ world
So there’s an important sense in which science isn’t about observing the
world.
It’s about trying ultimately to understand the world, but it sometimes involves
dealing with ‘idealized’ versions of it – versions which sometimes
incorporate assumptions that you know not to be true.
2. The nature of science
2.3 David Hume and the Problem of Induction
Not only does the philosophy of science warn us that we need to think about
what ‘observations’ and ‘data’ are, and that we’re not really observing the
world.
It turns out that the ‘common sense’ version of how theories are built up and
justified also isn’t as simple as it seems.
2. The nature of science
2.3 David Hume and the Problem of Induction
One of the key things that science does, on the common sense view, is produce
laws or generalizations, say like “All copper conducts electricity”.
These scientific laws consist of true, certain knowledge about the way the
world/universe actually is, and are based on a finite, but appropriately large and
varied, number of observations of particular instances of the way the world works.
So, given the following set of observations:
A bar of copper conducted electricity at time t1
A bar of copper conducted electricity at time t2
A bar of copper conducted electricity at time t3…etc
one is entitled to conclude that the following general statement is true:
All copper conducts electricity
2. The nature of science
2.3 David Hume and the Problem of Induction
However, David Hume (1711-1776) a Scottish
philosopher (and economist and historian) who
the Stanford Internet Encyclopedia of
Philosophy calls “the most important philosopher
ever to write in English”, pointed out a big
problem.
This problem goes by the name of “The Problem
of Induction”, though Hume himself didn’t quite
put it in those words.
2. The nature of science
2.3 David Hume and the Problem of Induction
Inductive reasoning (also called ‘inductive inference’) is “more of the same”
reasoning, and this is precisely what the common sense view says science is
doing – concluding that a general statement must be true/valid on the basis of
(a large number of) relevant individual statements.
So, again, given a suitably large and varied number of observations like a bar
of copper conducted electricity at time t1, a bar of copper conducted electricity
at time t2, etc., scientists have concluded that it is true that all copper
conducts electricity.
2. The nature of science
2.3 David Hume and the Problem of Induction
But in order to say that it is true that all copper conducts electricity, that is, in
order to say that we have a rational basis for the belief that all copper
conducts electricity, we need to justify that moment when we go from a finite
number of observations to the truth of some general conclusion.
We need to be sure that when we use inductive reasoning, we’re using a
method of reasoning that’s valid and which leads to the true, certain
knowledge that science is supposed to be about.
2. The nature of science
2.3 David Hume and the Problem of Induction
But Hume says that the required justification just doesn’t exist.
We’re not even entitled to conclude that the next piece of copper will conduct
electricity, much less that all pieces of copper will do so.
This is because there’s a problem at the heart of inductive reasoning.
Inductive reasoning depends crucially on the assumption that the future will be
like the past. Or, with respect to the above example, that future copper will be
like past copper in terms of conductivity.
But this claim (that future copper will resemble past copper) is precisely what
we’re trying to establish. And if your argument requires that you assume as part
of it the conclusion that you’re trying to prove, the argument is invalid. (This is
what ‘circular reasoning’ is (and, technically, also what ‘begging the question’ is).)
2. The nature of science
2.3 David Hume and the Problem of Induction
In actual fact, we all know from our daily lives that inductive reasoning isn’t
reliable. It isn’t a source of truth or certainty.
A famous (if slightly grisly) example of the unreliability of inductive reasoning
comes from the British 20th century philosopher Bertrand Russell, and goes by
the name of “Russell’s Inductivist Turkey”.
Russell’s Inductivist Turkey notes that on January 13th, he was fed at precisely
9AM.
He notes that on January 14, he was also fed at precisely 9AM.
The same thing happened day after day, and by August or so, the turkey used
inductive reasoning to conclude that “I am fed every day at 9AM” is true.
Then Christmas Day arrived, and the turkey was not fed at 9AM.
2. The nature of science
2.3 David Hume and the Problem of Induction
We use inductive reasoning all the time to get around in the world and to make
choices.
If I really didn’t think the sun was going to rise tomorrow, I wouldn’t bother doing
any work on next week’s lectures.
But people use lots of things to get around in the world (superstitions, prejudices,
insane hopes that have no chance of being true), and if science is on a par with
these, we’re in big trouble.
2. The nature of science
2.4 Why is all of this particularly important for linguists?
The scientific study of language in the modern era is a relatively young field (less
than 100 years old, as compared with chemistry, which has been studied
systematically for over 2500 years).
Other natural sciences have long-established practices and methodologies and a
rich tradition of investigation.
The study of language also can involve a far greater range of objects than many
natural sciences.
Linguists study everything from texts to introspective intuitions to statistical traits
of populations.
2. The nature of science
2.4 Why is all of this particularly important for linguists?
It’s vitally important that linguists have a good understanding of what science
really is, rather than relying on a ‘common sense’, and wrong, idea of what their
work entails.
In the weeks to come, we’ll highlight a number of issues and misunderstandings
that arise from this problem.