Please provide reference. That statement doesn't make sense. The cases where we know there is intelligence behind the design, support the contention that in cases where order and complexity occur and it's indeterminate if there was a designer or not, it's reasonable to conclude there was because cases we know of where intelligence was behind the design support the conclusion. There is no basis by which to conclude that there is no designer behind the order and complexity we see in nature because there is nothing in our experience to support that.
Looking at *nature* (the physical world) and declaring that order and complexity can exist without intelligent design because the universe exists and there is order and complexity in it (as the minuscule examples of something as simple as crystal formation) is starting with the idea that the universe came into existence without intelligent design. So one is, in effect, trying to prove the conclusion using the conclusion one wants to arrive at as the basis to support the argument. That is illogical. The universe can't give us an example of something that is orderly and complex without ID by the fact that it simply exists because that argument is based on a premise that cannot be supported in any way.
The way that ID is supported is that it is at least the logical conclusion that order and complexity in the man-made world indicate intelligence behind it, so order and complexity in the natural world indicate intelligence behind it. The only difference is a matter of scale. We create according to our knowledge and abilities; he does to his. We make cars and computers; he makes a universe.