I do not know why the members of the organizing committee of this conference have so cordially invited me — and not as an auditor but as a speaker. I am not a logician and I am not a philosopher of science. I suppose I have been brought here as a representative of the curious genus of semioticians, and probably the organizers thought that it would have been wise and witty to provide logicians with an ostensive example of what should not be done —in the sense in which, according to an example by Charles Sanders Peirce, a drunkard can be exhibited by the Salvation Army in order to advertise by contrast the advantages of temperance.