Vice President Joe Biden has spoken at-length about the devastating loss of his son Beau in 2015, but on Tuesday, he again shared his feelings when he explained why he didn’t run for president.

CNN’s Chris Cuomo asked the vice president if he at all regretted not putting his hat in the ring, knowing what he does now about the state of the race and the danger of a Trump presidency.

Giving a quick shake of his head, Biden said,

“I lost part of my soul when my boy died.”

Biden explained that he felt the presidency is such a massively important responsibility that a grieving father cannot fully take it on.

“You should never, ever, ever, commit to run for president unless you know you can look the people in the eye and say ‘I guarantee you, you have all of my being. You have all of my energy, all of my family’s energy to get this done. I wish I were a better man, but I just wasn’t ready to do that.”

They say that those who choose to lead are the least suitable to do so, and the Vice President has proven that many times over.

Watch.