## Interview with Donald Knuth

Nice surprise on my way to work this morning with an NPR story on Donald Knuth on the radio this morning. (Favorite quote: We are competing against ignorance).

## Comment viewing options

### Beaten to the punch.

Associated story also on Slashdot, though I don't see any quality comments just yet.

### Hero

Knuth is both one of my intellectual and Christian—specifically, Lutheran—heroes, which is awfully rare, of course. I was glad that they asked him if he believed in God, but it would have been even nicer if they'd noted that he wrote 3:16, a wonderful collection of world-famous calligraphers' impressions of all of the chapter 3, verse 16 verses of the Protestant Christian Bible; and Things a Computer Scientist Rarely Talks About. I certainly appreciate Knuth's humility in his faith and the systematic manner in which he approaches it (3:16 has been called "The Way of the Cross Section," which I love). Knuth is a national treasure, along with folks like Martin Gardner.

### Amen

Really, shouldn't we acknowledge that Jesus is the Ultimate Imperative?

### and pass the ammunition

Speaking as a pure functionalist... why not? Seriously, though, what I admire most about Knuth's religion is that he keeps it out of his professional life. For example, a cursory reading of his homepage gives no hints unless you count the pipe organ link.

### Secret Codes

Warning: now totally off topic.

sean: For example, a cursory reading of his homepage gives no hints unless you count the pipe organ link.

Which, if you're Lutheran like Knuth, you do. ;-) Obviously, other denominations have pipe organs, too, but it's a staple in Lutheranism—Bach was Lutheran (to put this at least nominally back on topic, so was Leibniz). The town that I grew up in, Columbus, Indiana, is world-famous for its architecture, and has dozens of churches with world-class pipe organs.

It's also an hour's drive from Bloomington, Indiana, home of Indiana University, which is home to Dan Friedman, Douglas Hofstadter, Raymond Smullyan, and no doubt others whom I'm forgetting at the moment.

Please pardon the nostalgia—it just occurs to me that having been born and raised a Lutheran computer scientist in southern Indiana was magical in a way.

### completely off topic

So do you think Friedman roots for the Cutters?

### More holy wars

Great move, Sam. Now you're going to start sports fandom wars.

Freeze! Step AWAY from the thread.... ;-)

### Website change

Let's make a website devoted to Christianity in computer science - jesus-the-ultimate.org

Just like the papers list, we could have a bunch of explanations of how Jesus is the ultimate X for X in {savior, friend, doctor, parent, lover, teacher}.

There are many binding constructs (lambda, pi, mu), but there is only one god - God!

### Isomorphism lacking

There are many binding constructs (lambda, pi, mu), but there is only one god - God!

What makes you think that? There seem to be a number of quite actively competing religions, if their ongoing flamewars, which get quite biblical at times, are anything to go by. It's not at all clear that the deity being fought over is the same one, in any meaningful sense of the word "same".

Of course, in recent times the major religions pay lip service to a sort of theistic equivalent of the Church/Turing thesis, in which a vague isomorphism between their respective deities is postulated. However, this certainly doesn't cover all religions, and we're still waiting for a formalization that can withstand peer review.

### Isomorphism

Regrettably a good point, although I would point out that in moderate Judaism/Christianity/Islam, at least, there's a recognition that we are "People of the Book," and that Yahweh/God/Allah are just various names for the One True God. Within that conception are various mysteries: the sefirot of the kaballah; the trinity of Christianity; no doubt similar Muslim mysteries that I'm not familiar with...

Once we include the various faiths' mystery traditions, the drive to unity becomes even more profound. Such traditions might be considered analogous to the drives to foundational calculi in computer science, concentrating on the aspects of divinity that are atomic and fundamental. And like such efforts in CS, these religious traditions often draw more heat from their brothers and sisters within the tradition than from members of other traditions!

### The explosive path to ultimate truth

There's a problem with the idea of unity in this area as having some deeper meaning. One of the major means for the achievement of this unity, historically, has been conquest of one sort or another. The belief systems of entire societies have been destroyed, suppressed, or sometimes assimilated, to help create the relative homogeneity you referred to.

There are multiple possible interpretations of the meaning of this. The popular one ultimately rests on the idea that conquest validates the beliefs of the conquerors, but this is both the most convenient for the conquerors, and the least likely to be true in any external sense. After all, if that were the case, then ultimate truth would be the belief system of whichever crazy cult finally succeeds in nuking the rest of us from orbit.

From this I conclude that there's good reason for a little humility here. Political correctness in these matters is actually a long-term strategy for avoiding being nuked from orbit. ;)

### Quite actively competing religions

There seem to be a number of quite actively competing religions...

Of which is exactly one the path to salvation, and all the others lead to hell! And there is no way at all to know which one is the right one! You can't figure it out, God can't quite manage to get His message across in a manner clear enough to be heard above Satan's din, so you've just got to gamble!

The joys of monotheism...

### :)

Of which is exactly one the path to salvation
:)

### push a continuation

so that when you find yourself at the gate of hell, you can backtrack..

### And my antihero...

If we care about programming language design, can we really admire the inventor of TeX? I suppose a reductio-ad-absurdum of the folly of using Stracheyesque macro systems to write large pieces of software has some value (a lesson relearnt by the autoconf folk), but even so, atrocities are atrocities...

### Stracheyesque

Does this refer to http://www3.oup.co.uk/computer_journal/hdb/Volume_08/Issue_03/080225.sgm.abs.html ?

### Yes, indeed

I didn't know it was online. Unfortunately the TIFFs give my ailing laptop a swap seizure and I can't read the texts. Any image gurus know how to turn the TIFFs into a manageable PDF format?

### macro TIFFs to PDF

I do this kind of thing regularly with ImageMagick. I used ImageMagick to view a couple of the Computer Journal pages, but with much tedious swapping. That took away my stomach for carrying out the entire job. The resolution is 800dpi, 1 bit per pixel, compressed with LZW.

Here's what should work:

    convert 225.tif 226.tif ... -density 800 filename.ps
ps2pdf filename.ps

It might save some swapping to reduce the resolution of the images one by one, prior to converting to ps. ImageMagick's convert or mogrify commands would handle that.

### What would you consider as a better alternative?

Never really delved into TeX, so I am not qualified to judge it from the standpoint of PL design. I know that it is quite flexible though and seems to be the way to go when you need to have exacting control for printing purposes.

### TeX as a programming language

As a general purpose language, probably not.

As a domain-specific language, TeX has succeeded in all counts--including the important metric of widespread use.

There are lots of things to pick apart about Tex. Macros (and it's reliance on them) are one (though the Tex macro system has been put to some tremendous uses, i.e. LaTeX and BibTeX). If I were Knuth, I would have avoided a whole slew of parsing ambiguities (which often show up as surprises to the user) by putting ALL backslash directives in braces-- \{foo} instead of \foo. And so forth.

However, to withhold admiration for something which has so profoundly benefited academic publishing because a system which has existed for over 20 years doesn't conform to the latest practices in software design is folly.

### Religious wars

Do we not have enough "religious" wars ( e.g. static vs. dynamic ) to contend with, without adding actual religion to the list?

I will leave personal salvation as an issue for personal consciences, but I know that the path to salvation for a community blog is to stay on topic, and not rise to troll bait.

### Didn't mean the subject as troll bait

I admire Knuth's humbleness in the subjects he approaches, be it text layout, algorithms, or pipe organs. Knuth would probably be the last to engage in a "religious" war on any subject.

### Original post is fine

Sorry Chris, didn't mean your original post, but rather some of the sub-threads. (You know who you are. ;-) )

### Heh

Sorry, guys. I just wanted to mention another dimension of my appreciation of Knuth's work, not start a totally off-topic debate. I appreciate everyone's insights and forebearance.