Did he think sheer guts and fighting spirit would keep them alive?

"The spirit keeps us alive," he said, "but sometimes you have to eat, too."

They hide the dead, even from themselves, that their spirits may not come to the lake and keep the fish away.

So long as this mighty spirit keeps them out of the ground, they are safe.

I believe such a spirit kept me from harm in the battle.

"But its spirit might have kept some of us alive through what happened next."

Only the defiant spirit of its people keeps the place alive".

The spirit held steady, kept his gaze firm and determined.

A spirit begging him to help keep that heritage alive.

The spirits of Mars, if there were any, kept their secrets to themselves.