How do you get into the sea?

A fool rushes headlong, is surprised by the temperature or force of the waves and has to spend some time adjusting, perhaps dangerously so. They may even decide too late, that this was a bad idea.

I wiser soul might first dip a toe. Then once they know what they're in for slowly move to waist deep. Once adjusted to the temperature and wave patterns, they might decide to go deeper. After years of doing this, they will become expert sea swimmers or surfers. But to follow their lead at that point as a beginner would be rash: they'd tell you to first dip your toe.

And so it is with knowledge. Short introductory texts are not meant to be authoritative or to give you immediate mastery. They are there to expose you to the core ideas in a way that might make you think "that's interesting", or perhaps recoil and think "that's not for me", and you move on.

There are many reasons why this is a useful approach.

Firstly, introductions to a subject are rare. My first programming book (it covered BASIC for 8-bit computers) was written for children, published by Usborne and consisted of less than 100 pages of quite well illustrated concepts. Where is the modern equivalent? Or the adult equivalent.

The web is awash with short introductory pieces written by amateurs that often leave the beginner more confused than where they started. Your local library is full of outdated material. A bookshop will have material that is popular but perhaps irrelevant (MS Word, Excel, etc. instruction manuals) or is intimidating for a beginner (700 page slabs on the intricacies of a subset of J2EE).

So where to start? The _Very Short Introduction to Computer Science_ and the _Very Short Introduction to Information_ appear from their ToCs to give somebody interested in those topics a quick overview. They are likely more in-depth and better written than the corresponding Wikipedia pages, and a reader new to it who is intrigued will make notes of topics on which to find perhaps more in-depth material.

Piqued, they may pick up a copy of _Very Short Introduction to Combinatorics_ and _Very Short Introduction to Big Data_ and make more notes, do a few MOOCs, pick up some Python and start a business that ends up employing thousands of people.

Or, alternatively, these introduction might clue them in that this isn't for them, and they might decide to pick up some texts on poetry, philosophy, geology or some other curiosity, and their life becomes a little better in another direction.

Would you rather say "no, you must dive into a multi-year programme of study on a subject from the outset", or insist that all information worth learning must be learned in its entirety? Is your argument boiling down to "if you're not prepared to commit to a doctorate thesis on it within 10 years, why bother"? It feels that way.

It's OK to be curious, to have a bit of interest in a lot of things. I am interested in chemistry and physics, but will never be a chemist of physicist. I am interested in learning more about pure and statistical mathematics, but I will never be a mathematician. Introductory texts that are entertaining and act as a stimulus, clue to the broader field, and jumping off point into the subjects should be welcomed, and for most of us, are.

After all, it was my dip in the toe of programming that led to my mostly satisfying and enjoyable career in computing that is about to reach its third decade...