Tim explains whether or not evolution and intelligent design are compatible beliefs:
Can intelligent design and evolution both be true? I guess that depends on what you mean by evolution and what you mean by intelligent design. In fact, this is the first Columbo question, “What do you mean by that?” What do you mean by evolution? Evolution can have a number of different meanings. Some are controversial, and some are uncontroversial.
For instance, evolution can mean change over time. It can mean change in gene frequency in a population. So we get some genes from mom and some genes from dad, and that's why our siblings look different. It can mean the mechanism of natural selection and random mutation. It can also mean limited common descent, that is, all dogs came from two dogs or all humans came from two humans. These are uncontroversial. We call these microevolution, and so these I think are compatible with intelligent design. In fact, virtually everyone agrees – even the most staunch young earth creationist – that this kind of evolution can be true and so can intelligent design.
Evolution can also mean universal common descent. That is, all organisms are related and go back to a common ancestor. Think of the evolution Tree of Life. But evolution can also mean that the evolutionary tree of life is true, but it's through an unguided process. I think this is where the definition of intelligent design and evolution may come in conflict.
We also need to ask what we mean by intelligent design because intelligent design is traditionally defined as certain features in the universe and in living things that bear the marks of an intelligent designer. So on this view, the macro evolutionary universal common descent idea could be compatible with intelligent design in the universe.
You have someone like Francis Collins. He's a theistic evolutionist. He believes that the evolutionary tree of life is true (macroevolution), but also believes that there's intelligent design in astronomy, in the universe, in physics, and so there would be an example of where they could both be true.
Where I see the conflict is where we have evolution being defined as an unintelligent process – undirected, purposeless, but unintelligent. That can't be true and also have intelligent design because intelligent design just is the marks of intelligence in living things. So, you can't have an intelligently unintelligently designed process. That's a contradiction. So, on most definitions of evolution, we see that they can be compatible with intelligent design. But in this one instance, you just can't put them together.