Who said 'if you haven't started on the Buddhist path then don't start at all'?

I recall a story that goes something like this > A Buddhist monk was giving a lecture on Buddhism. At the start he said > 'Who hasn't yet started on the Buddhist path?' Half the audience > stands. He continues 'To those people I say if you haven't started > then do not start. Please go to the entrance and your entrance fee > will be refunded'. Half the audience then leaves. He says 'to those of > you who are left who have started on the path I say you must continue. > Do not stop.' This is paraphrased but that's the essence of it. Has anyone heard of this and get the reference, the exact story and who said it. Is it true at all? Many Thanks as always