Etienne Gilson was a French philosopher and historian of philosophy, especially medieval philosophy, The book is about the kind of reality proper to paintings and their relation to the natural order. He writes in the own problem exactly what has a philosopher to learn from painting? This book, therefore, is the work of a philosopher asking himself philosophical questions on what he happens to know about a certain art. Just as we can philosophize about science, about history, or about religion, so also we can philosophize about art. The first chapter of this book will make clear, I hope, the reason it has seemed advisable to confine this inquiry to what philosophy can learn only from the art of painting.