Interesting, have you any examples of the methods ID uses to "determine design"? How successful have these methods (if they exist) been in differentiating between designed objects (such as a piece of nonrepresentational modern art) and natural objects (such as a snowflake)?
The philosophical assumption behind ID is that there may exist processes designed by intelligence. Naturalists don't allow the possibility that there may exist non-natural processes
You made an curious jump here from "designed by intelligence" to "non-natural". Do you think that intelligence cannot have a natural explanation? If it turns out that life on earth was recognizably designed then what basis would you have for excluding intelligent aliens (who evolved naturally on their planet) from being the designers?
Depending on how it is suggested that intelligent aliens are involved, Occam's razor.
And we don't yet KNOW, nor do we yet have "good evidence" (SETI as opposed to National Enquirer) that there are such aliens.
Don't run too far ahead of the evidence...
Cheers!
Likewise...
"E" types make the claim that it is possible to detect EVOLUTION by examining the information content of fossils. If the fossil is close in appearence to another one, it is EVOLVED. EVOLUTION uses only natural methods in the determination of EVOLUTION.