近代潛意識科學有一種說法是，我們的行為是由潛意識控制的，而不是由意識控制的。
How can this be,you might ask,when it so often feels as though we are consciously controlling our actions? Recent work by Daniel Wegner and Thalia Wheatley suggests an answer: the experience of conscious will is often an illusion akin to the 「third variable」 problem in correlational data.
你可能會問，這怎麼可能呢？我們自己的行為明明是我們的意識來控制的嗎。最新的一種解釋是：意識自由的感受，其實只是一種幻覺，產生這種幻覺的原因類似於數據算法裡的「第三變量」。
We often experience a thought followed by an action, and assume it was the thought that caused that action. In fact a third variable, a non-conscious intention, might have produced both the conscious thought and the action.
我們經常先是產生一個意識的思維活動，然後是對應的行動，於是理所當然地認為是這個意識活動引起了這個行為。但實際上很可能是第三變量，一個潛意識的意願引起了這個意識的思維活動已經對應的行為。
My decision to get up off the couch and get something to eat, for example, feels very much like a consciously willed action, because right before standing up I had the conscious thought 「A bowl of cereal with strawberries sure would taste good right now.」
例如，我決定從沙發上站起來去找些東西吃，這看起來完全是一個意識的決定，因為在決定站起來之前我的意識先是這樣想的：「一碗草莓拌穀物一定很好吃」
It is possible, however, that my desire to eat arose nonconsciously and caused both my conscious thought about cereal and my trip to the kitchen. The conscious thought might have been completely epiphenomenal and had no influence on my behavior, just as consciousness appears to be unnecessary in lower species in order for them to seek food and survive.
然而，可能的原因是，我想吃東西的欲望是潛意識升起的，並進而產生相對應的「去廚房吃穀物」的意識思維。這一從沙發站起去廚房的行為其實完全是由潛意識想吃東西而引起的，而「吃草莓拌穀物」的意識活動也許完全就是潛意識想吃東西的一個順帶產生的思維活動而已。這種情況類似於低等動物去找食物吃維持生存的情況一樣，低等動物靠本能去找食物，完全沒有意識參與的必要。
下面我們來對比潛意識和意識的主要區別之一：潛意識是實時對樣式進行檢測，意識是事後檢查、反省。
A number of psychologists have argued that the job of the adaptive unconscious is to detect patterns in the environment as quickly as possible and to signal the person as to whether they are good or bad. Such a system has obvious advantages, but it also comes with a cost: the quicker the analysis, the more error-prone it is likely to be. It would be advantageous to have another, slower system that can provide a more detailed analysis of the environment, catching errors made by the initial, quick analysis. This is the job of conscious processing.
有些心理學家認為潛意識的作用是儘可能快地對環境中的樣式進行檢測，並對其是好是壞給出判定。這樣的潛意識有其明顯的優點，但同時也有代價：分析的越快，越易於出錯。因此，如果能有另外一個速度較慢的系統能夠對外界環境進行更詳細的分析，並發現潛意識快速判斷所存在的一些錯誤，這樣對我們就會更有利。而這是意識的作用。
Joseph LeDoux, for example, suggests that humans have a nonconscious 「danger detector」 that sizes up incoming information before it reaches conscious awareness. If it determines that the information is threatening, it triggers a fear response. Because this nonconscious analysis is very fast it is fairly crude and will sometimes make mistakes.Thus it is good to have a secondary, detailed processing system that can correct these mistakes.
心理學家Joseph LeDoux認為人類有一種潛意識的「危險探測器」，能夠在外界信息到達意識層面之前對信息進行評判。如果它判定這個信息有危險，就會引發恐懼反應。由於這種潛意識的判斷非常快速和武斷，因此有時會犯錯。因此有一套能夠進行詳細分析以找出這些錯誤的第二套系統，是非常有利的。
Suppose that you are on a hike and suddenly see a long, skinny, brown object in the middle of the path. Your first thought is 「snake!」and you stop quickly with a sharp intake of breath. Upon closer analysis, however, you realize that the object is a branch from a small tree, and you go on your way. According to LeDoux, you performed an initial, crude analysis of the stick nonconsciously, followed by a more detailed, conscious analysis.
假如你正在戶外徒步旅行，突然看到路面上有一條長長的、光滑的棕色物體，你的第一反應是「蛇！」，你會倒吸一口涼氣並立刻停止腳步。等進一步分析後，你會認識到這個物體是一根長長的樹枝，於是你繼續前行。這種情形下，你首先是潛意識對樹枝進行了快速武斷的判斷，然後意識對樹枝進行了詳細的分析。