VERY SMART. like god like smart. Not physically to strong, so he needs help with physical work. He may be introverted and romantically clueless, but Senku wants to use his gifted mind and the power of science to protect and preserve humanity at any cost. Senku is by no means a bad guy. If he were, then he'd have easily gone along with Tsukasa's plan to ensure only young people were left to live in the world. He's also not an emotionless robot either. He shows signs of empathy here and there.