Hi Derrick,

"I don't think the argument actually has any implications for what we mean by the present - the present is just the current instant, regardless of whether what we are experiencing, perceptually, in the current instant is the world of the current instant or a mental representation of a past instant."

You appear to equate the present moment with the time at which light hits our eyes (before being processed and perceived/experienced). But why should we accept that this is the present moment? Why not, instead, at the time that light is reflected from its object/s, or somewhere in between, or even before that? On the other hand, I am saying that the present moment is the moment at which we are conscious/perceiving/experiencing, regardless of the content of our perceptions. To use your terms, I am saying that the present moment is after the processing "lag", and is the time at which we are (at which we find ourselves) conscious. You don't seem to disagree with this placement of the present moment, when you say that "the content of your perceptions in the present is the world of the past". The issue I have with this is that "the world of the past" implies that the present moment is not now when I am perceiving, but earlier when light hit my eyes. But again, what grounds do we have to consider this moment prior to perception as the present moment, such that the content of our present perceptions can be said to be of "the world of the past"? This is the implication for the present with which I am concerned.

"The last step doesn't say that our vision isn't an experience of the world, but that it is not a direct experience of the world. That is, it is stating that our vision is an indirect experience of the world, because it is merely a mental representation of the world."

If our vision only counts as an "indirect experience of the world", then what could possibly count as a "direct experience of the world"? What difference can you discern between a "direct experience of the world" and a mere "mental representation of the world"? Presumably, a direct experience is one which involves no time lag between light hitting our eyes and our perceptions, but this would not allow for any experience at all, assuming that some brain processing is required in order for us to have conscious experiences. The implication is that a direct experience can only ever be had with the so-called lag. Also, I'm unclear on what an "indirect experience" could possibly mean. If all experiences must be indirect, then what purpose does the distinction between "direct" and "indirect" serve?

"But if you agree that the content of your perceptions in the present is the world of the past, and also agree(?) that the world of the past cannot itself exist in the present, by definition, then this seems to me to lead inevitably to the conclusion that what you directly experience, perceptually, cannot be the world itself, and therefore must be merely a mental representation of it."

Again, if this is true, then what would count as a direct experience?

Luke.