Happiness researchers believe that positive emotions signal to us that we are in good shape. Our needs are being met, we have adequate resources, and we are reaching our goals. Positive emotional states also encourage people to engage with the environment, to seek out and take on new goals. We can contrast the effects of positive emotions with those of negative emotions, such as depression or fear. These emotions signal to the individual that something is not right, that the environment is not safe, and that the best course of action is withdrawal and avoidance.