Attitude and behaviour influence each other in a complex relationship. Attitude, which is one's thoughts or opinions, can predict behaviour when other influences are minimized, the attitude closely corresponds to the behaviour, and the attitude is strong. Conversely, behaviour can shape attitude through social roles defining behaviour and attitudes, the "foot-in-the-door" effect where small commitments lead to larger ones, and people justifying their actions to maintain consistent attitudes. The relationship is circular rather than strictly one-way, as behaviours and attitudes generate each other depending on the situation.