Weizenbaum says the list must be there, but may be empty: "Finally, the script writer must begin his script with a list, i.e., a message enclosed in parentheses, which contains the statement he wishes ELIZA to type when the system is first loaded. This list may be empty." page 42 of the 1966 CACM ELIZA paper.
And the MEMORY keyword "must be an ordinary keyword as well." So you'd need a (XYZZY ...) rule.
Also, the START symbol appears in the DOCTOR script, but is never mentioned in the body of the paper.
Another thing Weizenbaum doesn't mention in his description is the final empty list in the DOCTOR script. This does seem to be expected by the code.
And the MEMORY keyword "must be an ordinary keyword as well." So you'd need a (XYZZY ...) rule.
Also, the START symbol appears in the DOCTOR script, but is never mentioned in the body of the paper.
Another thing Weizenbaum doesn't mention in his description is the final empty list in the DOCTOR script. This does seem to be expected by the code.