Son Goku is first seen as a 12 year-old boy living in the wilderness. He is seemingly normal except his ignorance of the world, his great strenght and his tail. 

Goku was not greatly educated as a child as he never went to school. For most of his childhood, he lived in a remote location of the world. After Grandpa Gohan taught him artial arts, he began teaching him about things in the outside world (e.g. girls).

Regardless of Goku's lack of education, his strenght is in fighting. Goku can learn new techniques almost instantaneously. Goku's determinatiion to be the strongest he can be and love for fighting is what spurs him to excel, and ultimately makes him the greatest fighter in the Universe.

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