Take that rose bush, for example. We are all looking at the same plant, but our perception of it varies according to the way we each think and see. One person may see a vigorous rose, another may see a rose that could benefit from a little pruning, and a third may see a mess that no amount of attention would save. The rose bush isn't changing; it's the way we personally perceive it that differs, the way each of us thinks that colors our perception.