venerdì 5 febbraio 2016



  • La contestazione a S. : Plantinga claims correctly, we need first bare natural theology to argue for the existence of God (T) on the basis of all our background knowledge (K). Then, as Plantinga represents my style of argument, we must consider the probability, given (T& K), that (A) “God would make some kind of revelation …to humankind”–P( A/ T& K)... (B), “Jesus’s teachings were such that they could be sensibly interpreted and extrapolated to G”... (C) “Jesus rose from the dead”... (D) “In raising Jesus from the dead, God endorsed his teachings”... (E), “Jesus founded a church
  • Conseguenza. So call the probability that God endorsed the extrapolation of Jesus’s teachings in this way, given the previous evidence, P( E/ K& T& A& B& C& D). But to get the probability that G is true by this route on the only evidence we have (K), it is necessary to multiply these probabilities together
  • Esito: At each stage of multiplication, there will be a diminution of probability. Each individual... So the attempt to establish G by historical argument cannot give it a very high probability, not at all the kind of probability we need if we are “to know the great truths of the
  • Precisazione. Now, strictly speaking –as Plantinga acknowledges, but takes no further –P( G/ K) is the sum of the probabilities of the different routes to it. G might be true without some of these intermediate propositions being true.
  • Esempio. Maybe for example, in raising Jesus from the dead, God was not endorsing his teaching –so not-D; but God was endorsing only the teaching of the church which Jesus founded,
  • Regola generale. The more you say, the more you are likely to make a mistake. Yet G may be true without some of these conjuncts being true.
  • 2 repliche.
  • 1 the argument from dwindling probabilities applies, in so far as it does apply, not only to theological arguments, but to any argument of some length in history or science... consider a single page of a serious work of history, about the life of Julius Caesar for example, containing many propositions.
  • 2. My second point against the significance of “dwindling probabilities”is to note that the “dwindling”arises from the fact that in Plantinga’s discussion he supposes that all the evidence is put on the table at the beginning... Ma: as we add each conjunct to the hypothesis, we also add a new piece of evidence . In this way the probability may increase, not decrease.