Necessary conditions for agency
The results of our enquiry into the ingredients of intentional agency can be summarised in the following table:
| Category of Properties | Required Property for Agency | Bacteria | Protoctista | Plants | Cnidaria | Worms | Insects |
| Biological | Central nervous system (to allow fine-tuning) |
No | No | No | No, but nerve net permits rapid signal conduction | Yes | Yes |
| Sensory | Sensory capacities | Yes, but locomotion-driven | Yes (slow, chemical-based) |
Yes (slow, chemical-based) |
Yes | Yes | Yes |
| Memory | Memory capacity | Yes (3 seconds) | Yes (habituation) |
Yes (habituation) |
Yes (habituation) |
Yes | Yes |
| Flexible behaviour | Internally generated flexibility | No | No | Probably not, but very complex movements |
Not known, but possesses fast escape mechanisms |
Yes | Yes |
| True learning | Operant conditioning | No | No (habituation only) |
No (habituation only) |
No (habituation only) |
Not known. Capable of classical and instrumental conditioning |
Yes |
| Action | Motor fine-tuning | No | No | No | No | Not known | Yes |
| Representational | Indicators w. biological function; acquired by learning; capable of going wrong | No | No | No | Not known, but some jellyfish can see |
Yes | Yes |
| Normativity | Self-correcting behaviour | No | No | No | No | Not known | Yes |
Which organisms have mental states?
Based on the foregoing table, we can say that insects (at least, some of them) are capable of intentional agency, worms might be, while cnidaria and plants are probably not.
Outstanding problems
The main problems at this stage of our investigation are threefold:
First, the lack of rigorous criteria for some of our key terms: operant conditioning, fine-tuning and self-correcting behaviour.
Second, the lack of research data for many phyla of organisms (especially plants, cnidaria and worms) which would allow us to give definitive answers as to what they can and cannot do.
Third, the fact that we have so far failed to uncover a set of sufficient conditions that would warrant the ascription of intentional agency to an organism.
In the following section, I shall attempt to construct a model of operant conditioning which can only be explained in terms of agent-centred intentional stance. I shall use this model of operant agency to explicate the notions of fine-tuning, trying, self-correcting behaviour, belief and desire, and then attempt to construct similar models for other kinds of learning. My goal is to construct agent-centred intentional models of the following kinds of learning: