But its also a case where "perfect" exists. A case where you can, in principle, have perfect information about the internals of your bridge at any point. A case where you can, in theory, design the bridge to handle an infinite load from above.
In software, you can spec the behavior of your program. And then it is possible to code to that exact spec. It is also possible, with encryption and stuff, to write specs that are safe even when malicious parties have control over certain parts.
This is not to say that writing such specs is easy, nor that coding to an exact spec is easy. Heck, I would even doubt that it is possible to do either thing consistently. My point is, the challenge is a lot harder. But the tools available are a lot stronger.
Its not a lost cause just because the challenge is so much harder.
That kind of perfect is possible in math but not in software, which runs on physical machines and was written and verified by humans. It's like building your bridge inside a vacuum chamber with no entrances or exits—possible but not practical.
In software, you can spec the behavior of your program. And then it is possible to code to that exact spec. It is also possible, with encryption and stuff, to write specs that are safe even when malicious parties have control over certain parts.
This is not to say that writing such specs is easy, nor that coding to an exact spec is easy. Heck, I would even doubt that it is possible to do either thing consistently. My point is, the challenge is a lot harder. But the tools available are a lot stronger.
Its not a lost cause just because the challenge is so much harder.