Art is about using a medium to change how we see the world. Whereas design is changing how we live in it.
I have no pretense at knowing what art is or is not, but it is easy to draw draw a clear separation line between art and design by looking at their differences.
Artists and designers both use formal, intellectual, or material strategy to “produce” something of value. However, the major distinction between the designer and the artist is about accountability. In effect, they operate in very different frameworks of “rules”: the designer’s rules are mostly external and imposed by the problems to be solved, whereas the artist makes up its own rules. Artifacts from either discipline can resemble one another; however they result from very different motivations. Designers try to bring solutions to others’ problems; artists solve problems they themselves invent.
From a business stand point, the word “design” always implies that someone has carefully created some “thing” of value and that much thought and planning has been invested in a calculated and defined process throughout the project. Designers and engineers are very similar in that respect, as they must adhere to very intricate functional specifications in order to meet the project’s objectives.
Art on the other hand is a completely dissociated activity. An artist is supposed to portray a feeling, convey a message or inspire an emotion. An artist can express itself in any medium and color scheme, using any number of methods to convey its message. It doesn't have to adhere to any specific framework of rules, but rather creates its own. No artist ever has to explain the reason it did something a certain way other than by saying it was the way it felt.
Most design projects contain instructions detailing how to produce the expected “thing”. An artist can never be given any specific instructions to create a unique masterpiece; the composition simply flows from its hand.
Whereas design is based on external trends and influences, emotions are driving the movement of the artist’s hands and imposing the usage of the medium. Art produces completely unique “things”, when design is always re-producible.
Art has a meaning. It delivers a hidden message on purpose. Art is by definition unusable. Design reveals meanings. It highlights functions. Good design is usable.
Designers looking to create the “next” trend would be inspired if displaying some unique artistic prowess. They only have to keep in mind that uniqueness comes from passion and from refuting any rules that force to make even one choice that was unintended.
Expressing a message or an emotion inside a design project’s framework is a real challenge, but if met, it certainly contributes to a harmonious balance between art and design.