From a psychological point of view, learning constructive mathematics is agonizing, for it requires one to first unlearn certain deeply ingrained intuitions and habits acquired during classical mathematical training. In her book On Death and Dying psychologist Elisabeth Kubler-Ross identified five stages through which people reach acceptance of life’s traumatizing events: denial, anger, bargaining, depression, and acceptance. We shall follow her path.
Five stages of accepting constructive mathematics is a nifty introduction to constructive mathematics by Andrej Bauer. Mentioned by Martin Escardo on the Agda mailing list.