In a pluralistic society, consensus in spirituality must rest on a common human basis. The relevant social sciences as currently conceived cannot provide one. Bernard Lonergan's analysis of the human spirit – or intentional consciousness – elaborates the overlooked element in a psychological account of the human mind and, thus, grounds a psychology of spirituality as the natural expression of ongoing human integration, an account that is fully open to and, indeed, begs for theological elaboration. Initially unpacking the complexities of this matter and sketching a Lonerganian response, this paper focuses on the key complexity – the misidentification of the spiritual with the divine and the pervasive insistence, inherited from a pre-scientific age and perpetuated by Western piety, that first and foremost spirituality entails an explicit relationship with God. Treatment of a specifically Lonerganian topic – the suggestion that, because of the transformation effected by sanctifying grace in the human soul, consciousness includes a supposed fifth level characterized by the love of God – occasions an in-depth argument for the practical adequacy of a psychological treatment of spirituality apart from theological considerations. The ultimate goal of this argument is to establish, within a coherent interdisciplinary framework, an explanatory and normative treatment of spiritual issues, a science of spirituality.