Two strokes: a torso leaning into a step, legs apart. 人 is the script's simplest portrait — humanity reduced to the act of walking forward. As a radical (亻) it stands beside hundreds of characters, quietly making them about people.
人 opens Chinese philosophy: 仁 benevolence is 'two people' — you become fully human between humans. 人山人海 'people-mountain-people-sea' is every Chinese holiday crowd; 做人 'doing person-hood' means conducting yourself decently — an ongoing verb, never finished.
Two legs mid-stride — a PERSON walking toward you.
Add one stroke to 人 and you get 大 'big' (arms out) — the script builds 'great' from 'human' by opening the arms.