"It was implicitly supposed that every living thing was distinctively plant or animal; that there were real and profound differences between the two, if only they could be seized"

In this quote by Asa Gray, a popular 19th-century American botanist, the fundamental presumption of a distinct dichotomy between plants and animals in the classification of living organisms is attended to. This presumption indicates a historic scientific viewpoint where living things are thought to be unequivocally categorized into either of the two kingdoms: Plantae or Animalia. Gray points to an inherent predisposition or blind spot in this mode of thinking, recommending that during his time, the clinical neighborhood believed there existed basic and meaningful differences between plants and animals ("genuine and profound differences"), yet these distinctions were not plainly understood or articulated ("if just they could be taken").

This shows an age in the history of biology when taxonomy-- the science of classification-- was still establishing. Scientists looked for to understand the natural world by categorizing life kinds based upon observable attributes. This stiff classification system was deeply rooted in Aristotelian thought, which stressed binary distinctions and hierarchical structuring of life forms. Nevertheless, Gray discreetly reviews or concerns the clarity and accuracy of this dichotomy. By utilizing the word "implicitly", he suggests that such viewpoints were often considered granted without rigorous assessment.

The latter part of the quote ("if only they could be taken") suggests a sense of frustration or difficulty within the scientific venture. It acknowledges that while scientists intuitively believed in substantial differences, these distinctions remained evasive-- tough to define and capture through existing scientific approaches and understanding of the time.

In addition, this quote mean the complexity of life that modern-day biology acknowledges. Today, we comprehend that life can not always be neatly classified. There are organisms like particular protists and fungi that display characteristics of both plant and animal life, blurring the lines in between conventional kingdoms. Asa Gray's quote, for that reason, foreshadows the more nuanced and integrated understanding of biological diversity that would develop long after his time, acknowledging the limitations of strictly binary categories.