Identity and free will: Erikson and Baumeister

Erikson said identity develops across the whole life in eight stages. Each stage has a crisis (a conflict) to resolve. Resolving it well gives a healthy sense of self; failing leaves problems.

Strengths: it covers the whole lifespan, not just childhood. It recognises the role of society and relationships. Stage 5 helps explain why teenagers try out different identities.
Weaknesses: the ages are vague and people may not go through the stages in a fixed order. It is hard to test scientifically. It was based on Western society, so may not apply to all cultures.

Free will is the belief that we choose our own actions. Determinism is the opposite idea: our behaviour is caused by things outside our control, such as genes or upbringing.
Baumeister argued that free will is real as a psychological ability: it involves self-control and making rational choices, and it evolved to help humans live in complex cultures with rules.
Believing in free will makes people take more responsibility for their actions; studies such as Vohs and Schooler (2008) found that weakening this belief increased cheating.
Strengths: supported by experimental evidence; it gives a scientific way to study free will.
Weaknesses: free will is very hard to define and measure. Much behaviour may be caused by genes, upbringing or unconscious processes, so people may only feel free.