On Bottom Up and Top Down Thinking - Introduction

Neil's Note, October 2017: I've re-worked, shortened and updated this essay. It's still almost 5,000 words, but it's much better now. Please see http://www.honestcommonsense.co.uk/2017/10/bottom-up-versus-top-down.html.

(Neil's Note: This is the first part of an absolute monster of an essay - more than 8,000 words long. As explained below, I've decided to publish it in the form of 15-20 short sections, one every couple of days or so. Enjoy.)

Frequently, there are two opposite approaches to a task. One can be thought of as a bottom up method, the other as top down. And the bottom up approach usually works better – often far better – than the top down.

For example, there are two ways of teaching children to read: phonics and look-say. Phonics is a bottom up method. It builds up words and their sounds from individual letters and phonemes. Look-say, in contrast, is a top down method; each word is learned as a unit.

Now, look-say may enable a child to learn his first few words a little quicker than phonics. But those taught by phonics will eventually work out short cut methods, more like look-say, to quickly read words they have already learned. They still have the phonic method available to read words they haven’t seen before. However, the child taught by look-say has difficulty reading words he does not already know. So I think it no surprise that phonics produces, in the long term, vastly superior results compared with look-say, both in reading ability and in vocabulary.

Another activity which works better bottom up is engineering. Imagine, for example, a bridge builder who builds a beautiful arching span, leaving the foundations to be put in place later. Or, as computer scientist Arthur Norman has put it: “Building skyscrapers top down is kind of a delicate matter.”

These examples are by way of preliminary to my main theme: bottom up thinking versus top down thinking. I’m going to make a case that bottom up thinking produces better results than top down.

Further, I’m going to claim that the troubles of our current age are due, at their root, to a battle between two opposing mental forces. These forces are: enlightenment, which is associated with bottom up thinking, and endarkenment, which is the cause of top down thinking. I’m going to compare endarkenment to cancer. And I’m going to liken the promoters of top down thinking, that carry the disease, to cancer cells.

Moreover, I’m going to suggest that the cure for endarkenment is not merely enlightenment, but also Enlightenment. That is, that we must re-visit, dust off and re-polish the values of the 17th- and 18th-century Enlightenment, and carry them forward into the future.

These are large claims. This is also a large essay – more than 8,000 words. So, I have broken it into 20 or so small sections, each of which addresses a different aspect of bottom up versus top down thinking. My plan is, in the first instance, to publish each individual section, or group of a few sections, as if it was a separate essay.

I think of these individual sections as like bricks, which I have endeavoured to assemble – in a bottom up manner, forsooth! – into a wall. How well I have succeeded will be for you, the reader, to judge.