There’s an illuminating new piece in the SEP about 17th century theories of consciousness. (via) Your first reaction might be ‘what 17th century theories of consciousness?'; the discussion in those days was framed rather differently and it typically requires a degree of interpretation to work out what philosophers of the period actually thought about ‘consciousness’. In fact, according to Larry M. Jorgensen, who wrote the entry, the 17th century saw the first emergence of the concept of consciousness as distinct from conscience: in many languages the same word is still used for both.
Hobbes apparently sets this out quite explicitly (somehow this interesting bit must have passed me by when I read Leviathan because it left no impression on my memory); he has conscience originally referring to something which two people knew about (‘knew together’), and then metaphorically for the knowledge of one’s own secret facts and secret thoughts. Jorgensen tells us that the Cambridge Platonists had a role in developing the modern usage in English where ‘conscience’ refers to knowledge of one’s own moral nature while ‘consciousness’ means simply knowledge of one’s own mental content.
That idea, of having knowledge of one’s own mental content, seems to have a reflexive element – we know about what we know; and this was an issue for philosophers of the period, notably Descartes. For Descartes it was essential that my having a thought involved me knowing that I had a thought; but for some this seemed to suggest a second-order theory in which a thought becomes conscious only when accompanied by another thought about the first. Descartes could not accept this: for one thing if knowledge of my own thoughts is not direct, the cogito, Descartes’ most famous argument is threatened. The cogito claims that I cannot possibly be wrong about the fact that I am thinking, but if the knowledge of my thought is separate from the thought itself this no longer seems unassailably true.
It seems that while Descartes accepted that awareness of our own thought required some sort of reflection, he denied that the reflection was separate from the thought. He said that [T]he initial thought by means of which we become aware of something does not differ from the second thought by means of which we become aware that we were aware of it.
This can’t help but seem a little like cheating - sneaking in an extra thought for nothing. I think the best way to imagine it might be through analogy with a searchlight. We can swing the light around, illuminating here a building, there a tree, just as we can direct our conscious awareness towards different objects. Then Descartes might ask: do we need a second light in order to see the first light? No, of course not, because the light is already illuminated; if the light lights up other objects it must itself be illuminated (if perhaps in not quite the same way).
A surprising amount of Jorgensen’s exposition seems to be relevant to current discussions, and not solely because he is, necessarily, reinterpreting it in terms of modern concerns. In some ways I’m afraid we haven’t moved on all that much.