> Of course my engineer friends always talk about how you can never verify down to the chip level Well, I don't think that is the general case for software, th

> Of course my engineer friends always talk about how you can never verify down to the chip level Well, I don't think that is the general case for software, that people will manually assamble a bootstrap assembler from machine code (and how would you verify your editor? Maybe write to floppy and verify the bit pattern via electron microscope?) - and build up from there. Proving an entiresystem secure would be very hard. But to have parts that you can say "if I trust this, then it follows that I can trust all of these things that follow" is very useful. And so it is with hardware, too. Not to mention how useful it is to have a well documented, open platform (even if it's not libre), like eg the commodore Amiga 2000 that came with full schematics of the motherboard, along with measuring points, so it was feasible to find and replace faulty components, write drivers and build third party add-ons.