The Little Schemer

Hi, I am working through the little schemer. I do not have the math skills to work through SICP.

I have the following code:


(define (member? a lat)
  (lambda (a lat)
    (cond
      ((null? lat) #f)
      (else (or (eq? (car lat) a)
                (member? a (cdr lat)))))))


When I run this say like:
(member? 3 (cons 3 '(9 8 7 6 13 3)))

I get the following:
#<procedure:...my-scheme-log.ss:137:2>
rather than a list without the first instance of 3

Can you help me?

>>2
Though it runs against some styles, I prefer explicit lambdas under defines for this reason.
(define square
  (λ(x)
    (* x x)))
This is straightforward: "define 'square' to be a function that..." This is the style used extensively in The Scheme Programming Language. SICP seems to prefer the other format. I guess it is a matter of taste.