configure default paragraph alignment

[William Seager]

How do you set the default paragraph alignment to left 
justified (ragged right)? You can change individual paragraphs 
so they display (and print) with left justified paragraphs, 
but I want my documents to default to this. 
 
You can add "\raggedright" to the beginning of a
document, but that does 
not change the way lyx displays on screen (paragraphs 
appear fully justified but do not print that way). 
 
 any advice welcome, TIA,