I feel that each of these terms have very distinct meanings, and are therefore not interchangeable.
Smart is knowing facts and figures, the basic cornerstone of our educational system. Typical measures of how “smart” someone are grades and SAT scores. In other words, can they learn a set of truths, rules, and regulations and apply it to a standardized test?
Intelligence is knowing worldly matters, such as having interesting perspectives on life and existence. A typical measure of how “intelligent” one is is how much ethos one holds in a discussion. Basically, would I trust his or her life advice?
Clever is knowing how to get by, not by being the fastest or strongest, but just by holding on. A typical measure of how “clever” one is is how they deal with issues that arise: do they crumble or do they find a way to carry on?
The three definitely aren’t mutually exclusive, but they exist separately as well. Everyone can name a person who has a 4.5 GPA and 2300 SAT score but can’t hold a conversation for his life. Everyone can name a person who is a wasted philosopher, who has so much potential and promise but never applies himself. Everyone can name a person who is crafty and nimble, but is not regarded by everyone as untrustworthy and “street-smart” as opposed to “book-smart.”
Clever is what I aim for.