I have to chime in here about the safety of sharp, vs. dull knives and cutting utensils, and about age level required for a child to be trained in using a knife properly and safely.
First, let's look at accidental cuts. These are caused by inattention, or distraction, by carelessness, and by slippage.
Carelessness is when you are using the pinch-grip on your chef's knife, and feeding the food by small increments under the knife blade, using knuckles against the side of the knife to guide the knife. Inadvertently, one would let the thumb protrude into the blade path, or lift the blade too high, bringing the cutting edge down on a knuckle.
Another examle of carelessness is found by the cutter using a mandolin, and not paying attention, or not using safety guard to protect finger ends. You can see where this is going. The user slides the item to be slice back and forth across the sharp blade, and lets a finger-tip or two contact the blade, removing skin. Of course there are other careless mistakes that can result in cuts.
As for cuts made by dull knives, these typically occur when a blade slips along an item to be cut, rather than finding purchase and slicing through the item. The cutting edge can then slide right onto a thumb, a knuckle, or finger, depending on what cutting stroke is used. This creates a cut that is not as straight, and clean, and that will take longer to heal than a cut made with a sharp blade. That being said, a sharp blade can cut deeper than a dull knife blade.
For those prone to cutting themselves, there are cut-resistant gloves made for the kitchen industry.
As for the right age to introduce children to sharp cutting tools, well, that really depends on your ability to teach, and the child's ability to learn and follow directions. For me, that age was about 6 years old for my children, and the same for my grandchildren. They were able to listen, understand the concepts I was teaching them, and follow directions. They were also calm enough to not get frustrated with simple mistakes. i made sure that the items they were given to cut were not complicated, or challenging to push a knife through. I also started their training before eer giving them a knife. When they were still forbidden to touch sharp knives, I taught them that knives weere tools, not toys. I never let them use a knife that was too large for them to wield properly. And I taught them safe cutting techniques.
In summary, those who say that dull knives cause accidents. Those who say that carelessness causes accidents, well you are correct as well. Some children are ready to be taught basic cutting skills as early as 6 ears of age. My own children are proof of that. Children who are headstrong, or who can't yet understand the concept of knife techniques, and safety, well you have to wait until they are mentally, and physically ready. I know adults who shooed never be given a sharp knife.
As for understanding that children can learn valuable lessons at an early age, when my children reached the age where they could just start learning to crawl, I taught them the meaning of the word - hot. I fired up my Webber Smokey Joe with a full load of charcoal. When the coals were fully ignited, I picked up the child, placed his or her hand in mine, and brought it close enough to the heat source to be uncomfortable. I then pulled both of our hands away and said - hot. I did it three times in success. Not one of them ever went near anything that I pointed to, and said hot.
My observations are based on what I have both seen, and experienced in my life, blended with a little physics, and a bit of common sense. I hope that I haven't stepped on anyone's toes, and invite all to express their own opinions.
Seeeeeya; Chief Longwind of the North