A note on the definitions of 'theory' and 'hypothesis'

I occasionally enjoy debating the faithful on the subject of their particular beliefs. I won't say 'chosen beliefs', as nine hundred and ninety-nine times out of a thousand these beliefs are held simply because the person concerned has been told from a very young age that a) 'x is true' and b) 'questioning x is wrong and you will be punished for it'. Unfortunately powerful memes that do much to perpetuate faith.

It is a constant uphill struggle for those of us who value truth obtained through the analysis of evidence to get these people to look beyond their blinkers at the real world, but a rewarding one when it succeeds. One intelligent person saved from the darkness and superstition of blind faith is worth a hundred foolish converts.

Since Darwin (and Wallace) opened our eyes and showed us how all life could have arisen from simple origins, religiously inspired (or funded) researchers have been trying to show that evolution is wrong. They have had almost a hundred and fifty years to provide us with evidence that disproves the theory of evolution - none is so far forthcoming.

In the other direction, the more we learn about life, the more we study it, from the level of ecosystems, to whole organisms, right down to the level of their constituent molecules, the more evidence we find to support evolution. In fact, this evidence is now so overwhelming that even the Vatican has had to incorporate evolution into its official teachings of how God made us all. This fact might surprise some of the catholics I debate, and I would simply ask that they take a look at what the Vatican has said rather than listen to their own parish priests.

I say that this will surprise many catholics, because when I debate them, I often get asked 'if you don't believe in God, where did we come from?' or something similar. When I reply 'We evolved' I often receive the rejoinder 'but evolution is just a theory, right? it hasn't been proven.'

I have written this post specifically so that I can direct people I am debating with to it, in the hope that it will clear up this pernicious little mis-understanding.

When scientists speak of theories, they mean this in a technical sense. In its non-technical sense, a theory really is just an untested idea, like if I have a theory that the Conservatives will win the next election, for example.

In science, a theory is defined as a coherent group of general propositions used as principles of explanation for a class of phenomena.

When scientists have an idea that they want to test, they call this a hypothesis.

A hypothesis is defined as a conjecture put forth as a possible explanation of phenomena or relations, which serves as a basis of argument or experimentation to reach the truth: This idea is only a hypothesis.

(Source: http://dictionary.reference.com - link in title.)

In short, when lay-people think that evolution is not a fact, because it is only a theory, they have not understood that the word theory is used here in the technical sense of the term. They are thinking that evolution is in fact a hypothesis.

I note that this mis-understanding does not apply to other theatres of scientific endeavour: - I have never heard of a creationist who is scared to use a computer, or indeed switch on a light, because they doubt the theory of electromagnetism, or one who is scared to fly because they doubt the theory of aerodynamics.

Why, then, does this stupidity persist when it comes to the theory of evolution?

So please, after reading this, do not you tell me that you doubt evolution because it is only a theory, and remember, that in the technical sense, the idea of God is just a failed hypothesis.

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Anonymous said...

How do you solve infinite regression?

Dave said...

In what instance is it necessary to posit infinite regression? The only instance I can think of is that of positing a creator - in that case you have an infinite regress because it had to come from somewhere - the designer had to have a designer, who had a designer and so on, ad infinitum.
Is there anything in any of my posts that leads you to think I would be forced to invoke an infinite regress?