Philosopher David Hume was considered to one of the most important figures in the age of Scottish enlightenment. In "An Enquiry Concerning Human Understanding" Hume discusses the weakness that humans have in their abilities to comprehend the world around them, what is referred to in the title as human understanding. This work, now commonly required reading in philosophy classes, exposed a broad audience to philosophy when it was first published. A great introduction to the philosophy of David Hume, "An Enquiry Concerning Human Understanding" and the ideas within it are as intriguing today as when they were first written.