Sometimes stone knives would be lashed onto a bone or wooden handle for easier use.

FORBES: No. 1 The Knife

And even though it's been a very long time since the first knives were crafted out of stone, we haven't given up on that ancient manufacturing technique.

FORBES: No. 1 The Knife

To get his literary career rolling, Bushnell relied on veteran ghostwriter Gene Stone, who also has written other books, including "Forks Over Knives, " under his own name.

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