trusting trust considered harmful

http://cm.bell-labs.com/who/ken/trust.html
Ken Thompson, creator of UNIX
"You can't trust code that you did not totally create yourself."
C compiler could put an invisible backdoor in the Unix login command when it noticed that the login program was being compiled
C compiler could also add this feature undetectably to future compiler versions upon their compilation as well.
"I picked on the C compiler. I could have picked on any program-handling program such as an assembler, a loader, or even hardware microcode. As the level of program gets lower, these bugs will be harder and harder to detect. A well installed microcode bug will be almost impossible to detect."
"No amount of source-level verification or scrutiny will protect you from using untrusted code."

>>15
What if there is some secret quantum hardware to compensate for that? What if the NSA has released a spore of nanobots that pick up or alter circuitry at runtime when very specific conditions are met? What if the entire universe is a simulation and the simulator will always present the proper output and input only when it detects that it is being observed? What if God decides to spy on you and alters the physical properties of the universe itself only in your circuit when you aren't testing it?

You can never trust things based in nature.