Also see http://lambda-the-ultimate.org...
- What problem does this language solve? How can I make it precise?
- How can I show it solves this problem? How can I make it precise?
- Is there another solution? Do other languages solve this problem? How? What are the advantages of my solution? of their solution? What are the disadvantages of my solution? of their solution?
- How can I show that my solution cannot be expressed in some other language? That is, what is the unique property of my language which is lacking in others which enables a solution?
- What parts of my language are essential to that unique property?