Johnson was merely teasing Boswell, can't you see, Dick? Boswell was his dearest friend and constant companion -- and a Scotsman himself, with whom he went on an extended tour of the Hebrides; so Johnson was taking the piss out of him as close friends do to one another. You're surely not really so thick as to have missed that essential point -- assuming you to have read Boswell's great biography, and are not merely making unwarranted assumptions from a position of {genuine and literal} ignorance of your own; which I fear is what you are making it sound perilously close to.

Best regards as ever —

≈M≈