The 30-year-old actress was reading English literature at Cambridge University but dropped out in final year, reported Contactmusic.
"I had reached a juncture where I thought everything I had wanted to do at university had been done - make great friends and do a lot of theatre and work out what kind of grown-up I wanted to be - and I'd got to that point.
"Basically I thought, if I can make a choice like this which bucks the trend, and is different and now, I know that I'll be able to do it for the rest of my life. I'll feel proud of myself taking a different road," said Hall.
"And if I don't make the choice then I'll be on that trajectory of, 'oh, I got a degree from Cambridge, so here's my shorthand for being an intelligent person'. I wanted to do something that would make me feel stronger about making decisions that felt true and authentic and bold," she added.