Emil du Bois-Reymond's 1872 argument that science cannot explain consciousness remains relevant today. His position was rooted in an epistemological argument and a metaphysical skepticism, reacting against the speculative excesses of 19th-century German philosophy and natural science. Reconsidering his work reveals historical connections to the contemporary "hard problem of consciousness" and offers a vantage point for understanding how current open problems in consciousness studies have developed over time.
The notion of plant intelligence and sensation remains controversial in botany. Some scientists argue that plants exhibit sensory awareness, learning, memory, and communication, while others dismiss these claims due to a lack of neural systems and insufficient evidence. This paper examines the issue historically and epistemologically, tracing back to Darwin's 1880 book The Power of Movement in Plants, where he compared roots to brains and discussed plant sensation and behavior. The debate was already contentious in the nineteenth century. Contemporary arguments partly rely on post-Darwinian elements like biological continuity and analogy, creating an epistemological tension between avoiding anthropomorphic projections and recognizing that cognitive states could be realized in plants. Recently, animal ethics and non-Western animist views have been introduced to break the epistemological balance.