We all tell little fibs to get us through the day, from "I'm sorry I missed the big meeting; I was stuck in traffic," to "No, your butt doesn't look too big in that dress!"
Lies are also a big part of the dating ritual. We use them to get out of bad dates ("I'd love to go back to your place, but I promised to visit my grandmother in the hospital!") or to make ourselves sound smarter or more important than we really are ("After I earned my law degree at Harvard, I did a stint in the Peace Corps!").
The trouble with lying to a date, especially one you intend to see again, is that eventually, no matter how good of a liar you are or how small the fib might be, you're bound to get caught up in one of those lies. Like when he calls to check on your grandmother and hears club noise in the background, or when you run into his old roommate from community college.
Once you've been caught in a lie, it's hard for the other person to ever trust you again. The best relationships are built on honesty. So even if the truth is hard to say, suck it up and come clean.