Good Morning!
The key point in this lesson is "to help you clear your mind of all past associations, to see things exactly as they appear to you now, and to realize how little you really understand about them." This is an easy exercise to do all day long, as everyone and everything you see throughout the day is an excellent subject to apply the idea. If you do this, you may realize that just about everything you see is filtered through your mind first. Your mind searches its catalogue and comes up with some past association that seems suitable to the situation now, and thus you assign meaning to what you are seeing. For example, say today while you are driving around town, you see a homeless man on the street coming out of the bushes. First of all, how can you even label him as "homeless" unless you already have a clear picture in your mind's catalogue of what a homeless man looks like? After you have labeled him, then your perception kicks in and you decide how you feel about this man you are seeing. Your past acquired learning compels you to think to yourself thoughts such as "oh, that poor man", or "I hope he doesn't come up to my car and harass me", or "how can someone live like that?". While all this is going on in your mind, if you apply today's idea to the situation, you realize that you really don't understand anything about the actual reality of this man's existence at all.
Open your mind to being wrong about what you see today! There is a favorite line from A Course in Miracles' text that says: "I do not know what anything, including this, means. And so I do not know how to respond to it. And I will not use my own past learning as the Light to guide me now." It can be quite liberating to admit that you do not know what anything means.
Joan