Quotes from Fall 1995

Instructor quotes

Stupid/Humorous things my teachers told me (and everyone else in my classes) this semester.

We have a book. You buy it. You read it. That doesn't mean I'll follow it. I won't.--8-21-95
Here in the U.S. we have tests.--8-21-95
Student: I'm not sure about that.
Prof: Well too bad. I'm not going to prove it for you.--8-21-95
Student: Are we talking about reals?
Prof: What's the name of this class? Real Analysis. We will only be talking about the reals. [Actually, the course is titled Measure Theory.--cct]--8-23-95
The first four properties show that you can hardly see it and the fifth property shows that it is very big.--8-30-95
All these theorems hold for this space except all the ones that aren't true.--8-30-95
You may ask yourself in math "How can you have a theorem if you don't have anything?--9-1-95
I'm going to leave it for you to do this weekend. You have a long weekend. You have to do something on Monday, right?--9-1-95
x wiggles with y... x wiggles with itself.--9-1-95
This is a nice theorem. No hypothesis and we get a conclusion.--9-6-95
I said alpha and my chalk produced a zero.--9-8-95
If you want to be fancy about it you write "by the principle of mathematical induction," but that's the same as "dot dot dot".--9-11-95
That was just a preview of coming attractions.--9-13-95
Give yourself an epsilon. What else can you do?--9-13-95
Let me blabber here a little bit.--9-13-95
Oh! It's so easy I can do it.--9-13-95
I couldn't think of an interesting problem, so do this...--9-15-95
You ask yourself... or maybe you don't ask yourself. Maybe I just ask myself.--9-18-95
You don't want to shoot off to infinity.--9-18-95
I made all that advertisement last week about how you can't go wrong by giving yourself an epsilon, and then I forgot.--9-18-95
We should have a test sometime... Since I have to be gone on October 6... now you complete the sentence.--9-18-95
Let me write it out before I make a mess talking like this.--9-22-95
If everything were hunky dory, then we wouldn't do anything.--9-25-95
There is a serious defect with the calculus integral. One cannot live with it too long.--9-25-95
This is a Greek name so it must have some accents and probably some circumflexes, but I don't know where they go so I'm going to pick to put an accent here.--9-27-95
This theorem is so important that we will spell it out like this: T H E O R E M.--9-27-95
It's x wiggles with itself, blah, blah, blah, and all that stuff.--9-29-95
One way of the proof is obviously obvious.--9-29-95
I don't know. I was sleeping when I wrote that [on the board].--10-2-95
You can see we can do almost anything and not do it wrong.--10-2-95
Okay? Alright. Okay.--10-4-95
It is one of the theorems that is interesting but useless. Sometimes useless things are interesting.--10-4-95
...You remember that? [Complete silence] Yeah... come on, you couldn't have forgotten everything.--10-11-95
Quite a bit that is trivial on the real line is a theorem somewhere else.--10-11-95
We are actually going to use these two theorems later.--10-11-95
You all brought your homework? The grader must have gotten a little too excited and forgot to write down your grades in his book.--10-13-95
It's a proof by notation rather than ideas.--10-13-95
Corollary three is a corollary of corollary two which is a corollary of corollary one which is a corollary of the Monotone Convergence Theorem.--10-18-95
Approximate... Ah, that's too much to write, it's much easier to say we have...--10-18-95
In this measure stuff, when you put the chalk in your hand, 2^n comes out.--10-18-95
It turns out that the proof of that statement is shorter than the statement... We must be careful not to write down too much in the proof, or it will be longer than the statement.--10-20-95
"Do this" means "do what I have done".--10-23-95
That is truly a proof by picture that actually is a proof.--10-25-95
Very nice inequality.--10-25-95
This is very nice.--10-25-95
Jensen's inequality is a very pretty inequality.--10-25-95
That's Chebyshev's inequality, but I don't like that name because the inequality is so simple.--10-30-95
That gives us something that is useless for anything other than this example--11-1-95
We come to the main theorem in this business.--11-3-95
This one is a very pretty formula, as you will see.--11-3-95
We don't have all the tools we need to prove this, but it's just calculus... then again, you never prove anything in calculus either.--11-3-95
It's kind of a pretty inequality.--11-6-95
I'm not going to prove this theorem now. In fact, I may never prove it.--11-8-95
We are now down to calculus, like 161 (Calc I), but very shortly we will be out of it. The first line is 161.--11-8-95
This is a general statement like politicians make, which obviously isn't true.--11-8-95
Here is a useless theorem, but it may be interesting... I think it's
This is a general statement like politicians make, which obviously very interesting... I must admit it is useless since you will never, never in your life will you use it.--11-8-95
And our first step, I think I called that "step 1".--11-15-95
I have a little bit of a cold today, so let's see if we can put a proof together.--11-15-95
No, no, no, what am I doing here? What am I doing!--11-15-95
The proof of this theorem is half a line.--11-15-95
I can't talk [He had a bad cold] and I don't see any point in looking at you for an hour and you looking at me. Alright?--11-17-95
We do that with a little bit of a mistake. See, that's what's so nice about analysis. You can make little mistakes as long as they are under control.--11-20-95
Since we are running out of time, let me put wiggles in here.--11-20-95
We will have a take-home final during dead week. In our case, dead week will be very alive.--11-20-95
It's a very pretty inequality.--11-29-95
It's also a very pretty inequality.--11-29-95
Prof: I think this is the Weierstrass M-test which is really just one of those absolutely trivial results.
Student: Can you define absolutely trivial as opposed to just trivial?
Prof: Is that what I said?... Fantastically trivial.--11-29-95
If those people who write elementary calc books were honest... They throw around these big words like something is happening, but really nothing is going on.--11-29-95
I got your test done early so I figured I'd give it to you today instead of next Monday.--12-1-95
[Instructions for our take home exam:] You're going down the wrong track if your solution takes 50 pages. Don't turn it in.--12-4-95
[Instructions for our take home exam:] Do not say "I found this problem in such and such a book... Go look it up." That's not an acceptable answer.--12-4-95
This theorem is one of very few theorems that is self improving.--12-6-95
I can't write down here. The blackboard is too smooth.--12-6-95
This proof, like everything in this class, came out easy.--12-6-95
That's not necessary. That's not necessary here. That's not necessary.--12-6-95
That's a very nice inequality.--12-8-95
I don't know of any situation in analysis where if you have an iterated integral you don't flip it.--12-8-95
Prof hands out teaching evaluation and heads for the door to leave.
Student: What about our tests?
Prof: Oh yeah, I almost forgot to take your tests. Turn in your tests now.--12-8-95

Published quotes

Finally, here are some quotes from papers/books I have read for my classes and research this year.

There is no question of waiting for some future machine, because existing digital computers already have thoughts in exactly the same sense that you and I do. Well, fancy that! Philosophers have been worried for centuries about whether or not a machine could think, and now we discover that they already have such machines at Carnegie-Mellon....
Marvin Minsky of MIT says that the next generation of computers will be so intelligent that we will `be lucky if they are willing to keep us around the house as household pets'. My all-time favorite in the literature of exaggerated claims on behalf of the digital computer is from John McCarthy, the inventor of the term 'artificial intelligence'. McCarthy says even 'machines as simple as thermostats can be said to have beliefs'. And indeed, according to him, almost any machine capable of problem-solving can be said to have beliefs. I admire McCarthy's courage. I once asked him: `What beliefs does your thermostat have?' And he said: `My thermostat has three beliefs -- it's too hot in here, it's too cold in here, and it's just right in here.' --- J. Searle, Minds, Brains & Science, 1984, pp.29-30
These strengthening of our assumptions will occasionally be convenient but are hardly innocuous. The reader is invited to reflect on the empirical impact of these two conditions. --- J.C. Falmagne, "Psychophysical Measurement and Theory", Handbook of Perception and Human Performance, 1986, p. 1-30.
These patients can see the separate parts or properties of objects but seem unable to put them together. For example, one said, "I sometimes saw the different parts of the people as not, in a sense, belonging together....I remember one case where there was what seemed to me to be one object which was partly motor car, partly tree, and partly a man in a cricket shirt." Another said, "At first I saw the front part---it looked like a fountain pen. Then it looked like a knife because it was so sharp, but I thought it could not be knife because it was green. Then I saw the spokes...." Anne Treisman, "Properties, Parts, and Objects", Handbook of Perception and Human Performance, 1986, p. 35-61.
Just as reading is "externally guided thinking" (Neisser, 1967, p.136), so perception may be a form of controlled hallucination. Anne Treisman, "Properties, Parts, and Objects", Handbook of Perception and Human Performance, 1986, p. 35-61.
The fact that Holmes himself never observed a case of cerebral colour blindness does not impress, especially since he does not cite the evidence of those who did while, at the same time, being emphatic in his denial. Semir Zeki, A Vision of the Brain, 1993, p.63.
Best, in a work which with justice is rarely cited, had suggested that the perception of movement and of space may be the function of areas outside the striate cortex. But then Best had no evidence to support his claim, and his ideas on the organization of the visual cortex were themselves a trifle bizarre. Semir Zeki, A Vision of the Brain, 1993, p.83.
The equal of Henschen in the use of assertive phrases to dismiss uncomfortable facts, he wrote that Riddoch's statements were `certainly incorrect' since in `all my cases...the blindness was total...neither the presence nor the movement of any object of reasonable size could be recognized', a statement which would seem to leave out of account Holmes' own case 11 in the same paper. Semir Zeki, A Vision of the Brain, 1993, pp.83-84.
But they are far behind the times in believing that computational neurobiology can come up with theories that are of direct relevance to the neurobiologist, one which may be put to the experimental test, by ignoring the facts of the nervous system. Marr's book illustrates this perfectly. It is rightly prized for introducing a new way of looking at what the nervous system does, of defining its tasks. But at the same time, by ignoring the facts of the visual cortex, it renders the book of very limited value to anyone who might want to understand how the cerebral visual cortex might be undertaking the tasks thus defined, how it may be functioning. Semir Zeki, A Vision of the Brain, 1993, p.119.
But the manner in which the problem is posed by Marr and other computational neurobiologists is much too vague for the REAL neurobiologist, the one whose concern is to understand how a real nervous system undertakes such tasks. (Emphasis added). Semir Zeki, A Vision of the Brain, 1993, p.120.
Scientists like to believe that concepts are derived from facts. They like to portray themselves as deeply committed to the search for facts, unbiased and dispassionate in their collection of them, ready to renounce cherished beliefs and overthrow painstakingly constructed concepts if the new facts so dictate. Having so convinced themselves, they manage to convince others that this devotion to facts, no matter what the consequence, is the hallmark of their trade. A reading of the history of colour vision as it relates to the cerebral cortex would do little to justify this narcissistic image that scientists have of themselves. Semir Zeki, A Vision of the Brain, 1993, p.145.
Scientists speculate on these questions, only to discover that their answers were highly speculative. Semir Zeki, A Vision of the Brain, 1993, p.147
Scientists, like other groups, like to give difficult problems convenient labels. Having done so, they pretend that they understand the problem, which is therefore solved, at least to them. Semir Zeki, A Vision of the Brain, 1993, p.153.
Making inferences from clues is always fun in science, especially if the inferences turn out to be correct. Semir Zeki, A Vision of the Brain, 1993, p.165.
Finally, some usually use the term in quotes, a certain sign that, for good reason, they do not understand what it really means and cannot therefore communicate it to others. Semir Zeki, A Vision of the Brain, 1993, p.202.
Soon they realized that this was not the most fruitful occupation for scientists with a claim to eminence. Semir Zeki, A Vision of the Brain, 1993, p.202.
The chances that this was so were high, since it is difficult to believe that such a degree of order can be established by chance encounters with the visual environment. Semir Zeki, A Vision of the Brain, 1993, p.216. [And yet they believe this thing called evolution?]
Comparison of our results with the threshold curves of Arnulf & Dupuy shows that their contrast thresholds are about three times higher than our measurements, even when we repeated the experiment at their lower retinal illumination. However, considering the differences in the techniques, such discrepancies are small. --- FW Campbell & DG Green, Journal of Physiology, 1965.

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