Tumblr’s David Karp in 2007, Age 21.

Thanks to Quartz’s Zach Seward for jogging my memory about this oldie and goodie: Tumblr’s David Karp in a video interview taped in 2007, when he was 21, had 75,000 users and was talking about stuff like Digg, Flickr … and Twitter.

Karp’s interviewer is Howard Lindzon, who’s now known as the guy behind StockTwits. Assuming that the interview was taped close to the time it was published, it would have meant that the two men were talking as Karp was raising his first funding round of $750,000, led by Union Square Ventures and Spark Capital.

No need to say anything else: