His external exploration, regarding the senses, led Reid to his critical distinction between 'sensation' and 'perception'. While we become aware of an object through the senses, the content of that perception is not identical with the sum total of the sensations caused in our consciousness. Thus, while we tend to focus on the object perceived, we pay no attention to the process leading from sensation to perception, which contains the knowledge of the thing as real. How, then, do we receive the conviction of the latter's existence? Reid's answer is, by entering into an immediate intuitive relationship with it, as a child does. In the case of the adult, the focus is on perceiving, but with the child, it is on receiving of the sensations in their living nature. For Reid, the perception of the child is different from the adult, and he states that man must become like a child to get past the artificial perception of the adult, which leads to Hume's view that what we perceive is an illusion. Also, the artist provides a key to the true content of sense experience, as he engages the 'language of nature':