It was right then that I started thinking about Thomas Jefferson and the Declaration of Independence and the part about our right to life, liberty and the pursuit of happiness.

16 seconds sound clip from the The Pursuit of Happyness movie soundboard.

You can hear this line at 00:31:18 in the Blu-ray version of the movie.

Quote context

[...]

- Did you hear what I said?

- I have my things together, and I'm taking our son... and we're gonna leave now.

- I'm gonna put the phone down...

- Linda. Wait a minute. Hold it...

- We are leaving.

- It was right then that I started thinking about Thomas Jefferson and the Declaration of Independence and the part about our right to life, liberty and the pursuit of happiness.

- And I remember thinking: How did he know to put the pursuit part in there?

- Maybe happiness is something that we can only pursue. And maybe we can actually never have it, no matter what.

- How did he know that?

- Linda. Linda. (2)

[...]