Just begs the question, actually, but assuming the opposite is useless.
Evolutionary theory is not simple. Compare physics. Physics is very simple (not always easy, but simple).
I stated it for you in one sentence earlier. It's a simple idea. The ramifications get complicated, but it's that way with everything.
In physics we use mathematical models of what we perceive to be reality. Within the reality we define, the conclusions are factual, real, and true. As long as the axioms are true, everything else will be.
Yes and no. Reading along in a physics book like Feynman's lectures, you notice he starts with a simple model of something, takes some simple equation which springs from the model, and pushes and pulls it about. He solves for this and that, substitutes known equivalents for terms used within, and generally explores the ramifications.
But he often pauses to say something like, "This doesn't really agree well with experiment. Real molecules often fail to rebound with perfect elasticity because they can absorb energy internally so we will eventually need some refinements in the model. That, however, is for a later chapter..."
I merely paraphrase. It's been a while since I was poking around in that book. There is theoretical physics and experimental physics and the theory men never know when the experimental guys are going to come running in saying, "Hold it, folks! We have a major disconnect!"
In the late 19th century, all the axioms seemed to be true and physics was thought to be nearly a wrapped-up deal. Two blows fell from two different directions.
The Michelson-Morely experiment was to be the crowning achievement of Maxwellian theory, a measurement of the influence of the Earth's motion on propagation of light ripples through the ether. Ether was the stuff light waves were waving in at the time. If light waves were indeed ripples in some static substance which fills all space, that experiment should have detected the actual speed of Earth relative to the ether.
It didn't do that. That was when we learned that everyone, no matter how he is moving relative to anyone else, who measures the speed of light in a vacuum observes the same result. All the axioms had been true. Wave theory had "defeated" particle theory on the evidence to that point, such that Maxwell, when asked what happened to the particle theory, said that everyone who believed in it was dead.
Nobody knew what was right after the M-M experiment, but everyone could realize that the model which had been right up to then was somehow wrong. It took Einstein to come up with the best new model. While he was at it, he figured out that light in fact does act like a particle sometimes.
The blow from the other direction was a nonsensical theoretical result called the "ultraviolet catastrophe." A decent explanation of the details is in a section of the same name down the page on this site. In this case, the theory guy runs into the room and says, "The model is making a nonsense prediction. The model has always made sense before. We thought the axioms were true. We've been over and over the math! The output is utter nonsense!"
That needed some work by Planck to straighten out, a first step to quantum mechanics. Again, the model was wrong.
Evolution is not like this.
It's not physics, but it's in the same boat.
We must make many, many assumptions which are highly subjective.
It's got a simple theory and makes testable predictions. It probably would have been falsified by now if it were false. Instead, there's tons of evidence for it.
You cannot test it in a controlled environment.
Funny you would say that on a thread where we've been hammering the results of lab experiments into a particularly thick skull. It is routinely demonstrated in controlled environments. Read the thread and don't embarrass yourself.
Wishing does not make things so. Things are not anything you want them to be.