This idea is particularly difficult to believe at first. Yet it is the rationale for all of the preceding ones.

It is the reason why nothing that you see means anything.
It is the reason why you have given everything you see all the meaning that it has for you. 
It is the reason why you do not understand anything you see. 
It is the reason why your thoughts do not mean anything, and why they are like the things you see. 
It is the reason why you are never upset for the reason you think. 
It is the reason why you are upset because you see something that is not there.
Old ideas about time are very difficult to change, because everything you believe is rooted in time, and depends on your not learning these new ideas about it. Yet that is precisely why you need new ideas about time. This first time idea is not really so strange as it may sound at first.

Look at a cup, for example. Do you see a cup, or are you merely reviewing your past experiences of picking up a cup, being thirsty, drinking from a cup, feeling the rim of a cup against your lips, having breakfast and so on? Are not your aesthetic reactions to the cup, too, based on past experiences? How else would you know whether or not this kind of cup will break if you drop it? What do you know about this cup except what you learned in the past? You would have no idea what this cup is, except for your past learning. Do you, then, really see it?

Look about you. This is equally true of whatever you look at. Acknowledge this by applying the idea for today indiscriminately to whatever catches your eye. For example:

I see only the past in this pencil.
I see only the past in this shoe. 
I see only the past in this hand. 
I see only the past in that body. 
I see only the past in that face.

Do not linger over any one thing in particular, but remember to omit nothing specifically. Glance briefly at each subject, and then move on to the next. Three or four practice periods, each to last a minute or so, will be enough.