I'm surprised Wittgenstein hasn't been mentioned here. He thought and wrote extensively about the foundation of mathematics. In fact, the write-ups of a series of his lectures features discussions between him and Turing (and other luminaries) about what maths is about (and W tends to come over stronger on the subject):

https://www.amazon.co.uk/Wittgensteins-Lectures-Foundations-...

It's great fun to read.

This seems to set up some interesting parallels to the Tractatus, but I don't think it does so in a way that improves our understanding of software engineering. I'm tempted to put it in the "not even wrong" category, but I'm worried that may be too harsh, and I may need to go back and think on it some more.

Incidentally, computer-types may be interested to know that Alan Turing sat in on some of Wittgenstein's lectures on the foundations of mathematics, and they didn't quite see eye-to-eye.

http://www.amazon.com/Wittgensteins-Lectures-Foundations-Mat...

Edit: excerpt here: http://www.turing.org.uk/philosophy/ex4.html