If you think too hard on what fruit is you'll get a headache. You would think it a no-brainer to simply declare that fruits are apples, bananas, oranges and pears, right? Who picks up a ripe tomato and calls it anything but a vegetable, but guess what...tomatoes are botanical fruits.
Apparently there are differences between botanic fruit and culinary fruit. In botany, fruit is the part of a flowering plant that disseminates its seeds through ovary tissues. Therefor botanists have determined that certain foods such as corn, wheat and beans qualify to be lumped into the fruit category.
Fruits are naturally loaded with fiber, water and vitamin C (and of course, sugars). The potassium in fruit can help avoid developing such adverse health conditions as kidney stones and bone loss. Consuming fresh fruit might also reduce risks of development of cancers, dementia and cataracts. Much research is available concerning the nutritional value and health benefits of fresh fruits, in other words, the information is out there, you just have to let it sink in.
I suspect most of us are quite content with the layman definition of fruit meaning the sweet flesh of an apple, strawberry or peach.