Plant Thinking: A Philosophy of Vegetal Life and Minimal Cognition in Plants

“We stand outside of science. Instead, we stand before a tree in bloom, for example — and the tree stands before us. The tree faces us. The tree and we meet one another, as the tree stands there and we stand face to face with it. As we are in this relation of one to the other and before the other, the tree and we are. This face-to-face meeting is not, then, one of these ‘ideas’ buzzing about in our heads.”  – Heidegger


This session will balance the philosophical considerations of what a plant is, with scientific considerations of plant behavior. Plants are in many ways considered an ‘other.’ This ‘otherness’ stems from their apparent inability to think (lack of cognition) or ability to move. The session will include two speakers, one to consider the philosophy of plants and the other to speak about advances in sciences of plant behavior. A discussion will follow to discuss concepts of plants as ‘other’ as well what it means, to think.

Research is beginning to show that plants do present a state of minimal cognition. Although lacking a nervous system, they move chemical signals through their stems and roots, reacting to stimulus, learning, competing, and cooperating. The cell structure of a plant cell is different from that of an animal cell; this difference seems to allow for a direct cell to cell transmission of chemical signals without the necessity of a nervous system.

Through the release of chemical signals, plants have evolved ways to “speak” to insects, attracting specific insects at different times to assist in protecting the plant. Plants are able to detect the root systems of other plants of the same species, and the root systems of plants of different species; some species aggressively invade the “territory” of another species, while respecting the territory of another plant of the same species. This ability to detect and respond, even to communicate with insects and other plants, begins to minimize the separation between the vegetal from ourselves.


Redrawn from Bunger,1983. Trees of different species attempt to invade the territory of the other.

Plants also demonstrate the ability to move. Although rapid movement exists in only a few species of plants, such as the venus fly trap, or the sensitive plant, all plants move and adapt to their environments. The roots of plants forage for nutrients and water in the soil. Once sources are found, roots proliferate in places rich in nutrients and moisture. The tips of the roots actively move through the soil, and the rest of the root systems maps that path through the ground.

Through discussions of tropisms and philosophies of the ‘other,’ we can begin to discuss what it means to think, where cognition begins, and what it means to be different.


Michael Marder is a research professor of Philosophy at the University of the Basque Country, Vitoria-Gasteiz. He studies the philosophy of plant life through the phenomenological tradition (the philosophical study of the structures of experience and consciousness). He is an editor of three book series including Critical Plant Studies.

Dr. James F Cahill is a Professor of Biological Sciences at the University of Alberta. His research includes plant behavioral ecology, competition, plant-pollinator interactions, insect and mammalian herbivory, and evolutionary and functional ecology.

Transduction Themes

Eco/Matter Theory

Cell Signal Transduction




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What Plants Talk About

Trailer to Fancis Halle’s Il Etait une Forêt

Albino Redwood

Proposed by Gwendolyn McGinn.