arguments for intelligent design

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Arguments For Intelligent Design

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Arguments For Intelligent Design. In recent years American theologians have responded vigorously to Darwinian claims by putting forward an alternative that they believe provides a better account of why living organisms appear so well adapted to their environments - PowerPoint PPT Presentation

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Page 1: Arguments For Intelligent Design

Arguments For Intelligent Design

Page 2: Arguments For Intelligent Design

• In recent years American theologians have responded vigorously to Darwinian claims by putting forward an alternative that they believe provides a better account of why living organisms appear so well adapted to their environments

• According to its critics, Darwin’s theory of evolution and modern versions of it simply cannot explain how certain how certain features of animals evolved

• The alternative theory that they propose is termed Intelligent Design, and its supporters present it as a scientific project aimed at demonstrating that living things have been designed by an intelligent designer, and are not simply the result of the improbable processes of evolution

Page 3: Arguments For Intelligent Design

• According to supporters of Intelligent Design, such as Michael Behe and William Dembski, science can only go so far in its understanding of how organisms developed over time

• Darwinian theory, they argue, becomes unstuck when it tries to give details of how an organ as complex, yet perfectly adapted, as the eye evolved

• Charles Darwin himself admitted as much, when you acknowledged that it seemed ‘absurd in the highest degree’ that something as sophisticated as an eye could have evolved through natural selection

• There just doesn’t seem to be any way that the eye could have evolved from something more primitive

• As Richard Dawkins puts it when summarising this criticism, ‘what use is half an eye?’

Page 4: Arguments For Intelligent Design

The answer proposed by Intelligent Design supporters is ‘none’, in which case evolutionary theory, which tries to show how an eye might have evolved from more primitive light-detectors, is dramatically undermined:

how did a spot become innervated and thereby light-sensitive? How did a lens form within a pinhole camera?...None of these questions receives an answer purely in Darwinian terms. Darwinian just-so stories have no more scientific content than Rudyard Kipling’s original just-so stories

William Dembski

Page 5: Arguments For Intelligent Design

Dembski

• A just-so story is a backwards-looking explanation that isn’t supported by any evidence – it’s just a neat and tidy explanation that fits in with the theory

• Dembski’s criticism of evolutionary theory is that it makes lots of noise about how things like eyes evolved, but that it cannot substantiate these claims by showing how the parts of an eye might have evolved and come together with such spectacular success across the animal kingdom

Page 6: Arguments For Intelligent Design

Michael Behe• Behe uses the term ‘irreducible

complexity’ to refer to those features of nature which are so complex that they cannot be explained in evolutionary terms

• He doesn’t believe that evolutionists have shown how imperfect and simple light-detectors gradually become complex and perfect eyes

Page 7: Arguments For Intelligent Design

• Behe’s claim is that irreducibly complex features such as the eye are made up of parts (lens, retina, rods, cones) that form a highly successful unit – but that these parts on their own would be useless in evolutionary terms; they would not lead to success

• The only explanation for their existence is that these units came into being fully formed as a whole, and did not go through any evolutionary process

• Behe gives an analogy to help us understand irreducible complexity:

Page 8: Arguments For Intelligent Design

He asks us to consider a mouse-trap, and how the various parts of it work together to create a functioning whole unit: the base, the metal spring, the holding bar, the catch. If any one of these parts were missing or worked less efficiently, then the mouse-trap would fail to work. The mouse-trap only functions when all its parts are in place, and we know this is how the designer designed it. In the same way, a complex feature like an eye only functions when all its parts are in place. Working backwards from this complex unit towards a simpler one, as evolutionary explanations do, results in these parts being removed or made less efficient, and the eye would cease to function. Evolutionary theory, therefore, fails to explain how well-adapted features like the eye came about

Page 9: Arguments For Intelligent Design

It turns out that irreducibly complex systems are headaches for Darwinian theory, because they are resistant to being produced in the gradual, step-by-step manner, that Darwin envisaged

Page 10: Arguments For Intelligent Design

• The conclusion drawn by Behe, Dembski and their colleagues is that complex features such as the eye can be explained only if we posit the existence of an intelligent designer, God, who deliberately created these units with a specific function in mind

• Saying that there exists an intelligent still allows for scientific research programme, as proposed by Behe, that seeks to identify the irreducibly complex component parts, to analyse them and determine their functions and interrelationships

Page 11: Arguments For Intelligent Design

Because of the scientific presentation of Intelligent Design theory there were campaigns across the United States to introduce Intelligent Design into the science curriculum to be taught alongside evolution. In 2005 a significant test case was brought to court by the parents from Dover Area School in Pennsylvania. The parents objected to the teaching of Intelligent Design alongside evolutionary biology in science – they argued it was a form of creationism and had no place in science. The court heard evidence form a number of adaptationists (supporters of Darwin’s theory) and from Intelligent Design supporters, including Michael Behe. After several months the judge ruled that Intelligent Design was not a science and he barred its teaching from science classes.

Do you agree with the judges decision??

Page 12: Arguments For Intelligent Design

Criticisms of Intelligent Design• One significant problem of Intelligent Design is that it’s had

difficulties identifying a clear instance of a feature which is irreducibly complex

• The eye is often given as a paradigm example of irreducible complexity, and supporters of Intelligent Design refer to Darwin’s own difficulties in explaining how ‘half an eye’ could be evolutionary successful

• Darwin wrote that the claim that an eye as a product of evolution seemed ‘absurd in the highest degree’ – although he does then go on to explain in painstaking details how the eye could have evolved by gradual degrees

Page 13: Arguments For Intelligent Design

• Dawkins attacks the assumption (made as part of the principle of ‘irreducible complexity’) that features like eyes cease to function if a part of them is removed

• Someone who has their sight damaged might not be able to drive a car, but may be able to see well enough not to walk into a tree or over a cliff

• Partial sight is useful and it gives an evolutionary advantage over competitors who are unsighted. Hence, in organisms that lack sight, a gene sequence that results in partial-sightedness will be more successful in reproducing than zero-sighted competitors, and the genes will spread through the population

• Each mutation that leads to a refinement and improvement in the eye will spread through the population in the same way

Page 14: Arguments For Intelligent Design

• With evidence stacking up in favour of an evolutionary explanation for design, Intelligent Design has to look elsewhere for examples of irreducible complexity, mindful of Dawkins warning:

Do not just declare things to be irreducibly complex; the chances are that you haven’t looked closely enough at the details

Page 15: Arguments For Intelligent Design

Criticism 2• Intelligent Design is not a

science at all

• It’s not been accepted by the scientific community (many of whom are religious) in so far as no research carried our under the banner of Intelligent Design has been accepted into a peer reviewed academic journal – the key marker of respect from the scientific community

Page 16: Arguments For Intelligent Design

• It might be objected that that there is a global conspiracy to against Intelligent Design, but the explanation given by editors is that Intelligent Design does not follow scientific methodology: it does not carry out rigorous testing in tightly controlled experiments,, or make definite predictions based on its theory; it lacks consistency and generally any scientific utility

• The defence offered by supporters of Intelligent Design is that it’s still in its infancy. But until it publishes some original, peer-reviewed, research it looks like remaining very much a non-science