"Perfect rationality" (according to book) is same as what we mean by "intelligent" it means the agent is

rational and all its choices are optimal. This implies that the agent knows all it needs to about the environment.

"Random" means all actions are selected with equal probability. Implies no knowledge is used.

"Meta" means one system level or degree of freedom out.

&optional and &rest and &keyword are used to have varying or optional arguments in a Lisp function.

(defun length (l)

(if l (+ 1 (length (rest l))) 0]

(defun count (x l)

(if l

(if (equal x (first l)) (+ 1 (count x (rest l)))

(count x (rest l)))

0]

(defun flatten (l)

(if l

(if (atom (first l))

(cons (first l) (flatten (rest l)))

(append (flatten (first l))

(flatten (rest l]

(defun append (l1 l2)

(if (null l1) l2

(cons (first l1)

(append (rest l1) l2]