(define every?
  (lambda (pred lst)
    (if (null? lst)
      #t
      (if (pred (car lst))
        (every? pred (cdr lst))
        #f))))

(define all-positive?
  (lambda (lst)
    (every? (lambda (i) (> i 0)) lst)))

(define every?-c
  (lambda (pred-c lst c)
    (if (null? lst)
      (c #t)
      (pred-c (car lst)
        (lambda (b)
          (if b
            (every?-c pred-c (cdr lst) c)
            (c #f)))))))

(define all-positive?-c
  (lambda (lst c)
    (every?-c (lambda (i c) (c (> i 0))) lst c)))

(define not-all-positive?
  (lambda (lst)
    (all-positive?-c lst not)))