The Scandal of Induction
The
movement from particular observations – if I drop this pencil it will
fall – to general laws – if I drop any pencil it will fall– is called
induction and it is one of the basic elements of science.
Imagine
you’re an alien and want to find out what human beings have inside their heads.
You would not want to do experiments on every human being to find out if they
have a brain inside their skull: smashing open everyone to check for the
presence of a brain would take a long time and cause a lot of mess. So you
would smash open only a few hundred thousand heads and, on the basis that all
the rest of the human beings are pretty much like the ones that you have
smashed open so far, you would probably conclude, not unreasonably, that all
human beings have a brain inside their head.
However,
the philosopher Hume pointed out a critical problem with this method. Taking
the example of the sun rising on a daily basis we assume that it will rise the
next day simply because it has always done so before. But there is really no
logical reason for it to be this way. Just because it’s always happened this
way, that doesn’t mean that it can’t change. To carry on with the destructive
theme, imagine that a huge blazing meteor were to collide with the Earth
tonight and obliterate the planet. If that were to happen, there would be no
sunrise tomorrow.
To
use a more down to earth example: before the 16th Century everyone
in
Hume’s
criticism of induction is often simply known as “Hume’s problem” or the scandal
of induction and it poses a real problem for science as all of the universal
laws generated by science rely on induction.
The
Solution?
Karl
Popper offered a potential solution to this problem by thinking about the way
we do science in a new light. Essentially, Popper turned science on it’s head
by claiming that we are looking at science in the wrong way. Instead of looking
at science to provide us with theories that are definitely true Popper said
that we should be looking at science to provide us with theories that we have
failed to prove false for a very long time. This approach to science is called
Falsificationism.
Fundamentally,
Popper accepts that science can never provide us with complete 100% certainty
but, he claims, this is not really a problem because that is not actually science’s
job. The job of science is simply to provide us with a theory that is likely to
be true based on the fact that we haven’t yet managed to prove it wrong. One
unfortunate consequence of this, however, is that you can only ever be certain
of the things that you have proved wrong. We know, for example, that the world
definitely is not flat. The problem with this fact is that, although certain,
it is not actually that useful to know that something is definitely false.