To arrive at the edge of the world's knowledge, seek out the most complex and sophisticated minds, put them in a room together, and have them ask each other the questions they are asking themselves.
Efforts to change the way we think—and to enhance our cognitive capacity—are ancient. Brain enhancers come in several varieties. They can be either hardware or software, and they can be either internal or external to our bodies. External hardware includes things like cave paintings, written documents, eyeglasses, wristwatches, wearable computers, or brain-controlled machines. Internal hardware includes things like mind-altering substances, cochlear implants, or intra-cranial electrical stimulation. Internal software includes things like education, meditation, mnemonics, and cognitive therapy. And external software includes things like calendars, voting systems, search engines, and the Internet.
I've had personal experience with most of these—save cave painting and the more esoteric forms of hardware—and I think I can say with confidence that they have not changed my brain.