So when I think about Billy's life philosophy earlier in his life I see him as having a mainly nihilistic viewpoint (certainly fatalistic), but exhibiting the happiness that you would generally associate with existentialism if you see them as competing viewpoints. That is, up until after his plane accident. For the first time in what we would conventionally think of Billy's life he feels that he has a true goal in his life: to inform people of the wonderful insights into the nature of time that the Trafalmadorians have helped him understand. "The cockles of Billy's heart, at any rate, were glowing coals. What made them so hot was Billy's belief that he was going to comfort so many people with the truth about time" (35). We see a definite switch from Billy as someone who has a lot of trouble finding enjoyment and purpose in his life to someone who has a definite mission: to spread the truth.
I wouldn't go so far as to say that this is a religious experience for Billy, but I would go so far as to say that his discovery of the Tralfalmadorians has been a spiritual experience of Billy. There are a lot of similarities to someone who claims to have recently undergone a spiritual transformation. Instead of finding Jesus Billy finds the Tralfalmadorians. He goes onto late night talk shows and starts to write his knowledge down in the form of open letters. And it all brings him a great deal of happiness. While I think it's impossible to say whether or not we should interpret Billy's interactions with the Tralfalmadorians as real events, they do give us interesting and useful insights into Bill as a character.
I wouldn't go so far as to say that this is a religious experience for Billy, but I would go so far as to say that his discovery of the Tralfalmadorians has been a spiritual experience of Billy. There are a lot of similarities to someone who claims to have recently undergone a spiritual transformation. Instead of finding Jesus Billy finds the Tralfalmadorians. He goes onto late night talk shows and starts to write his knowledge down in the form of open letters. And it all brings him a great deal of happiness. While I think it's impossible to say whether or not we should interpret Billy's interactions with the Tralfalmadorians as real events, they do give us interesting and useful insights into Bill as a character.