Genius

From the Oxford Dictionary online:
'genius'

/jeeniss/

• noun (pl. geniuses) 1 exceptional intellectual or creative power or other natural ability. 2 an exceptionally intelligent or able person. 3 (pl. genii /jeeni-i/) (in some mythologies) a spirit associated with a person, place, or institution. 4 the prevalent character or spirit of a nation, period, etc.

— ORIGIN Latin, also in the sense ‘spirit present at one’s birth’, from gignere ‘beget’.

Everyone has heard the expression "...great minds think alike". but what does it mean? What is it referring to? Do great minds really think alike? If all minds thought alike, would we still get innovation? Genius can also be defined as:
= intuis (wisdom)
= cognis (knowledge)
= technis (practical ability)
and in addition, those people are often in possession of a 'special vision'. How valid is an IQ test? IQ?Is it just a social construct? What does it measure exactly - capability/cognitive ability? What about emotional intelligence?

Wikipedia 'Genius'

What about madness? Yhey possess a 'special vision'...are they just geniuses with an inability to communicate their vision effectively?

The question remains: Are you a mad scientist...or an evil genius?