I'm very against wearing scarves during the summer; they make your neck sweaty on hot days. But now that it's officially fall, you're permitted to break them out with reckless disabandon. While it's not quite cool enough for a full-on knit wool number, a lightweight one will look seasonally appropriate with a dress, boots, and a cardigan. Maggie Gyllenhaal strolled around New York City yesterday afternoon with husband Peter Sarsgaard in what we think is the perfect fall outfit. Click through to find a thin plaid scarf to add to your closet.