PayPal Co-Founder Peter Thiel Urges Class of 2016 to “Do What Hasn’t Been Done” - The entrepreneur told graduates that when PayPal was founded “we learned that doing new things is difficult, but it is possible.”
Commonly Confused Words
since / because
Since is often used to mean because: "Since you asked, I'll tell you." Its primary meaning, however, relates to time: "I've been waiting since Tuesday for the letter." Most people now accept since in place of because; however, when since is ambiguous and may also refer to time ("Since she went to college, he found another girlfriend"), it is better to use because or after, depending on which you mean: "Because you are intelligent and careful, your writing has improved since the beginning of this course."
SOURCE: Nesbitt-Johnston Writing Center