We all know the old saying about how if you give a man a fish he eats for a day, but if you teach him how to fish you feed him for a lifetime. But there are a few more steps involved in making a meal, you know, like slicing that fish open to cook it. Fortunately it turns out we can add one more line to that adage, because if you give a man one specific fish he can turn it into an actual knife that can cut up all the other ones he caught.

This video from the YouTube channel kiwami japan—which we came across at RocketNews24—shows how to turn dried bonito (katsuobushi), considered the hardest food in the world, into a working, very sharp knife. After weeks of drying the fish out and letting it ferment, it becomes hard enough to use as a hammer (what a versatile fish!), but it can also be worked into a strangely beautiful cutting tool.

Normally we wouldn’t recommend playing with your food or your knife, but in this case all we want to do is cut up stuff with our strange fish tool. Although we have to admit it would be strange to come home to smell fish baking in the oven only to find out we were having “knife” for dinner.

But hey, you know the old adage: give a man a fish and he might turn it into a dangerous weapon. Oh wait, no, that’s not a real saying. But it should be now.

Would you prefer to eat this fish or make it into a knife? Tell us why in the comments below.

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Featured Image: kiwami japan