A few years ago I wrote an online column for Red Herring. The gig was interesting, but after a change of editorial regime, they decided to stop the experiment. The pieces all kind of disappeared after a while, and I realized that some of them were actually pretty good. Heaven knows I spent plenty of time on them.

So if for no other reason than to have easily-accessible copies of them, I'm going to start reposting them here. Most were from 2004, so they might seem a bit dated; but I think some of the ideas are still worth playing with.

Knowledge is power. For a long time we thought it was something immaterial, cerebral, almost otherworldly. No less a figure than Plato argued that the world of things and appearances was but a dim reflection of another world of ideal types, more real than reality itself. But Plato's theory is too good for this world. Knowledge is also things, and actions.

One of the key events in twentieth-century philosophy was the discovery that the Platonic model of knowledge was incomplete. In mathematics, Kurt Gödel demonstrated that mathematics could never be a perfectly self-contained, exhaustively proven system. For decades, philosophers and mathematicians had worked to find the fundamental foundations of mathematics; Gödel's incompleteness theorem showed that the search was fruitless.

The critique continued in philosophy. Cambridge University's Ludwig Wittgenstein, arguably the twentieth century's most influential philosophical mind, argued that the meaning of language arises from its use, rather than from its logical properties. A few years later, British philosopher Michael Polyani coined the term "tacit knowledge" to describe things that we can know but can't effectively communicate. Tacit knowledge, Polyani argued, is an important component of skilled work, and even shapes activities that we traditionally have thought of as entirely logical (like science).

Historian Thomas Kuhn's Structure of Scientific Revolutions took Polyani one step further, and opened up a whole new front in the assault against traditional notions of knowledge. Structure reconceived science as a puzzle-solving activity guided by a mix of formal methods and cultural norms, and punctuated by dizzying revolutions and paradigm shifts. Sociologists of science, cultural anthropologists, literary and gender theorists, all used Kuhn as an inspiration to their critiques of objectivity.

You would think that after all this, the Platonic model of knowledge would be dead and gone. But it lives on in information technologies.

David Sifry is best-known as founder of Technorati, one of the flagship social software services. However, David has been in high tech for a couple decades, as CTO