Science News has an intriguing article on what we might call ‘plant psychology’ as some biologists are increasingly thinking of our green leafy friends in terms of their memory, communication and behaviour.
On a related note, an edition of ABC Radio National’s All in the Mind from the end of last year focussed on the ‘psychology’ of bacteria.
These sorts of discussions are the interesting result of our current most popular way of understanding the mind: the cognitive approach.
This attempts to explain the mind in terms of an information processing system, so mental processes are defined in terms of how they perform computations.
For example, memory is the process of encoding, storing and retrieving information. Perception transforms sensory data, such as light spots on the retina, into elaborated experiences; and attention selects which channels of processing to prioritise.
In its most basic, and somewhat caricatured form, the cognitive approach says our minds are just calculations because we have been able to successfully describe what parts of it do using maths.
But if the mind is just calculations, it makes it very difficult to say what is and what isn’t a mind.
If something learns, reacts and communicates, all of which can be described in information processing terms, than many things could be described as having minds. Computers, plants, bacteria, perhaps even whole ecosystems.
Indeed, many of the big debates in psychology (consciousness, intentionality and so on) are attempting to define the mind outside of the computation metaphor, and this is where the hard work lies.
Discussions about whether plants have minds make us think about how we define our own minds, as simply saying ‘a mind is what humans have’ doesn’t help us understand how to make sense of them.
Link to Science News on plant cognition.
Link to All in the Mind on bacteria cognition.
Mind Hacks 
That¬¥s one of the unwarranted conclusions derived form the cognitive approach: “panpyshism” or everything potentially can have a mind.
But maybe is more deep than all that and it refers to our inherent tendency to anthropomorphize reality.
Lets assume for a moment that everything is a computational system. I think most would agree the processing ‘power’ of plants in this context is more constrained than humans. Therefore, although everything may be a computational system, not all computational systems may have a ‘mind’. That is, perhaps a what we view ‘as’ a mind require additional properties such as Turing completeness, or some other emergent property arising from the foundations of computation.
The cited article was quite enlightening. While some researchers are using terms like plant neurobiology the research discussed was more concerned with establishing that plants are capable of reacting to and changing their environments and even altering their reactions based on previous encounters. The point seems to be a strict “animal, vegetable, mineral” categorization blinds us to research that supports an expanded notion of the capabilities of plants rather than speculating that they might have minds or processing powers approaching simple animals much less humans.
The anthropomorphism charge doesn’t really stick, at least not across the board. Their working definition of behavior doesn’t require intention; they aren’t really assigning human characteristics to non-humans. When computers came into common use in the 1980’s “memory” was adopted as a description of one of their capabilities. This had more to do with the evolution of language via analogy than considering computers as living or conscious beings. Throughout history humans also have had a tendency to see themselves as above all other types of living beings and acted in ways that have proved detrimental to other species when safer alternatives would have served our immediate needs just as well. Perhaps this sort of research will help us re-align our policies to the benefit of all life on the planet.