In Subtraction Isn't Always Less, Ann Hudson examines her father's last several years living with idiopathic Parkinson's Disease, his childhood which he re-participated in as a result of his Lewy body dementia, and his shifting presence as her father. The poems consider his identity as a scientist, as well as the science of his increasing fragmentation. While a grievous loss, his death re-configures how his family understands and experiences him: an endearingly monolithic head of a family, an athlete, a musician, an expert in his field. Through a sharp and tender observation of landscapes both physical and emotional, along with a generous offering of data, curiosity, and awe, Hudson shows us how death might bring someone we love into a more precise and present focus.