If I have some non-empty language $L$, is $\epsilon \in L$ always true by definition? Is there a good place to read about the formal definition of a Language (aside from wikipedia)?
2026-03-26 21:08:07.1774559287
On
Is a non-empty Language required to contain the empty string by definition?
1.2k Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail At
2
There are 2 best solutions below
0
On
According to this answerer, no, even though $\emptyset \subset S$ in set theory, this does not mean that $\epsilon \in L$.
No, the empty string need not be in the language. A formal language is simply a set of strings over a finite alphabet, with no restrictions on the set.
If you Google "formal language theory" you'll get lots of hits. I did so, and this chapter looks pretty good.