This book argues that for the two chosen mystics, Mantak Chia (Taoist) and William Blake (Christian), sexual feeling (energy) is vital for developing the mystical consciousness necessary to arrive at an end state of 'unity''. Their alchemical systems are broken down into a tripartite model that represents the whole person. Both tripartite models incorporate the brain, heart and sexual regions. Ultimately, this book shows that within their alchemical systems, sexual feelings play a role as a vital ingredient, starting point and catalyst in producing the end state of ''unity''. This conclusion is based on a critical comparative analysis of their respective practices and poetry using primary accounts and secondary literary sources. The text also comments briefly on the implications of their systems for an aspirant leading a chaste or married life.