It mentioned how he wanted to write a book about what was going on but just couldn't put the words down. It also mentioned how he had written a series of article for a large newspaper about the things that were happening. But it wasn't until he went and lived with the Okies in California in their camps and saw their faces and saw how they were living like livestock that he was able to start writing.
While this is one of my very favorite movies, my mother absolutely hated this movie as she grew up in the Depression. I still remember when I was little hearing derogatory remarks about Okies. I'm reminded of this in the movie when, after an encounter with the police and the Joads are driving off, the cop says, "Okies... they ain't human."
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I found this Guardian article that excerpted more of Steinbeck's writings about the plight of emigrants to California. This is exactly what the documentary I saw the other night was reading from complete with still pictures including the a picture of the woman lying on the dirt floor in this passage:
"Four nights ago the mother had a baby in the tent, on the dirt carpet. It was born dead, which was just as well because she could not have fed it at the breast; her own diet will not produce milk. After it was born and she had seen that it was dead, the mother rolled over and lay still for two days. She is up today, tottering around. The last baby, born less than a year ago, lived a week."And another still, black and white pic was shown of this family:
"The spirit of this family is not quite broken, for the children, three of them, still have clothes, and the family possesses three old quilts and a soggy, lumpy mattress. But the money so needed for food cannot be used for soap nor for clothes.
With the first rain the carefully built house will slop down into a brown, pulpy mush; in a few months the clothes will fray off the children's bodies, while the lack of nourishing food will subject the whole family to pneumonia when the first cold comes. Five years ago this family had 50 acres of land and $1,000 in the bank. The wife belonged to a sewing circle and the man was a member of the Grange. They raised chickens, pigs, pigeons and vegetables and fruit for their own use; and their land produced the tall corn of the middle west. Now they have nothing."http://books.guardian.co.uk/extracts/story/0,6761,643450,00.html