Oxford and Cambridge Lecture Out-takes



This lecturer seems to have a tautology problem:

  • “A mapping is 1-1 and onto if and only if it is 1-1 and onto.”

From a lecturer who knows exactly what he intends to do:

  • “….and now we need to increase n. The best way to increase n is to increase n.”

Obviously a student who didn’t like his lecturer:

  • “I didn’t think he could live down to his reputation, but he did.”

Another dissatisfied student?:

  • “Oh dear, where’s my rifle….”

Referring to exams? I hope not…:

  • “…because if you’re dead earlier, you certainly are dead later on…”

Good helpful instruction here:

  • “You could sort a sequence by assigning 1,2,3… to it. That’s the fastest sort routine I know of!”

Confused medium?:

  • “Please yell out if there are any typing errors”

In the middle of a difficult proof:

  • “This is the stage where I start to pray”…
    followed by…
    “Somebody up there is being kind to me, are they? No.”
    followed by…
    “I’ve done something silly with a square root of 2.”

Guess which subject:

  • “I have a personality disorder: I don’t like to assume things are measurable.”

More Lebesgue Integration quotes:

  • “You can sleep if you want.”
  • “It’s delicate to get your hands on it.”
  • “Will we all agree to shut that one in a cupboard?”
  • “Well we can’t quite stop yet – although I am tempted…”

Sounds too good to be true:

  • “This is fun: lots of magical ways to solve differential equations!”

Any idea of the context of this one?:

  • “If you watch T.V. you see there are such things as Marathons”

A disillusioned lecturer:

  • “In the old days, the pure days…”

A weensy big headed, are we?:

  • “I’m just showing off, seeing how fast I can do them…”

Some quotes from a statistics lecturer:

  • “This is a stupid example – you can see why; it’s an exam question.”
  • “We observe approximate approximation to …. “

A hopeful Rings and Groups lecturer:

  • “… a cube, so it has 8 faces … “

A lecturer nicknamed ‘Hurricane’:

  • “OK? Well, not very ok but you can find the mistake yourself”
    followed by…
    “Whatever you need to get the answer”

An undergraduate talking about Fermat’s last theorem, so I am told…:

  • “A millionth of a second is virtually forever”
  • “It doesn’t really make a lot of difference between 8 and 33”

Yet *more* Lebesgue integration quotes:

  • “Integration by parts is not economical on paper”
  • “I can’t be bothered. Can’t we just go back and……”
  • “It’s all so simple it’s hard to remember”
  • “I worked it out last night – let’s see if it works in the daylight”

This term’s contradictions prize:

  • “I want to stop looking at inhomogeneous equations and start looking at inhomogeneous equations”

Nope, this isn’t ‘Hurricane’:

  • “Imagine me running towards you at root-three-over-two c”

Physicists? Thick?:

  • ” ‘3+1′ is physicists’ notation for ‘4’ “

You’ll never guess what – we had an incredibly quotable Lebesgue integration lecturer:

  • “Has anyone got it out yet? (Pause) You’re not doing it are you?”
  • “It looks an incredibly integrable function”
  • “Proof’s easy, by the way, provided I keep my act together”
  • [to a moving blackboard] “SIT!!!”
  • “Sorry about that – I’m teaching this to some engineers…they’d have a fit if they saw” [a Lipschitz condition]
  • “My mind’s gone crazy again”
  • “I’ll just reassmble the duster”
  • “Take the computer and it will do lotsof things while you’re at the pub”
  • “In lectures, everywhere you have chaos”

Some quotes from a Rings and Groups lecturer:

  • “Examples come in two types: interesting ones and examination ones”
  • “This [z->conj(z)] is worse than bad”
  • “Now I run down the r’s and up the b’s”
  • “Just send one of the 1st years to check…”

A confuddled lecturer:

  • “Is this the right lecture theatre?”

Do I really need to tell you where these came from?:

  • “The proof is not required for finals, but I’m going to give you it anyway because it’s nice.”
  • “multiplied by the stupid derivative dFx”
  • “I’d thought we’d spend the rest of the day in light entertainment: Let’s do some schools questions!”
  • “Questions are easy, with a bit of luck”
  • “Tonelli would tell us…” (undergraduate) “No he wouldn’t, he’s dead”
  • “Knock that sign for 6 and use Tonelli somewhere”
  • “If you want to cut corners, an intelligent corner to cut is not to learn the proofs of any of these theorems”
  • “And that’s the singularity that’s going to save our bacon”
  • “I’ll take a special delta when I see what I need”
  • “And the Riemann-Lebesgue lemma zaps it again”
  • “I am falling into a trap. I assume I know it’s there – I want to fall into it”
  • “If x were negative this would go sky-high – it would blast off the map”
  • “Can I bring along an elephant and some trumpets to draw your attention…”
  • “Pinch yourself, kiss your neighbour, anything to draw attantion to this” (loud kissing sound of student kissing neighbour)
  • “Let me make a mistake now”
  • “Meanwhile back at the ranch…”
  • “It’s my lucky day!” [after a double-cancelling error]
  • “I actually like integrating”
  • “I love integrating” [Referring to previous lecturer]
  • “That woman can’t clean the board. I pay someone to clean the floor at home and then I come here and spend 15 minutes mucking around”
  • “We could do it if we could pull the sum sign through and that’s what God gave us the monotone convergence theorem for”
  • “…and at this stage your heart should have a slight hiccup”
  • “…and at this stage you should go and have a beer”
  • “I’ll massage this into a shape you can use the MCT on”
  • “Now we go into automatic drive and finish this off”
  • “I’m going to use this diagram. It’s not completely silly”

After turning out all the lights:

  • “So that’s what these switches do!”

From analysis lectures:

  • “The fact they’re called divided differences suggests that they are the difference of 2 things divided by something”
  • “10! is fairly small”

A different quotable lecturer:

  • “Are you bored?” [Students shout Yes]
  • “Are you mega-bored?” [Students shout YES]
  • “What a waste of life is coming to Oxford to get bored in lectures.”

A talkative lecturer:

  • “No, let me stop gibbering my mouth off without thinking about it beforehand… and I’ve just shot myself in the foot”

Obviously good at making mistakes:

  • “I’ve just realised I’ve done something crazy…in the notes this time”

A sad lecturer’s tale:

  • “I used to be quite clever – it’s the drink”

Proof technique obviously ok:

  • “Well I guess that’s a respectable proof actually”

More of the prolific lecturer:

  • “You keep thinking you’ve got over the hiccups and then they come back again”
  • “I like it. (referring to a lemma) It looks upside down to me.”
  • “…there’s the following delicious little proof”
  • “I’ve got two 2’s, the third should be a 3”
  • “Let’s fall into the trap – let’s do the obviuos thing”
  • “(referring to a function) It looks like a case of Carling Black Label”
  • “The trick is not to write anything”
  • “Ugh. This is horrid, isn’t it”
  • “It will enable you to pull derivavtives through integrals, which you have wanted to do all your life – and some of you have been. This tells you when you can legally do it.”

Who said proofs were legal?:

  • “Watch this proof carefully – it looks like a confidence trick”

Remember continuity and differentiablity?:

  • “In other words this is going to be a 3 epsilon proof.”

Referring to Lorentz:

  • “It’s a garden trellis type transformation”
  • “To be consistent, call it *^(-1)”
  • “We get our own back by calling rotations in the plane ‘Pseudo-Lorentz’”

From a computing lecture:

  • “A degree’s worth more than a monitor”

In a differential equations lecture:

  • “As you can see, these equations are very easy to remember – hold on, I’ve missed out a term…”


From a groups lecture:

  • “It’s a bit like probability except that it can go negative and the integral is not normally 1”
    and “I can’t possibly tell you what this is – it’s a very unpleasant space”

Starting off a course early in the year:

  • “The important thing to remember about this course is that it doesn’t actually mean anything.”

My, my! Here’s a helpful topology lecturer:

  • “I’ll prove it with a diagram, and next time I’ll translate it into pictures.”

From a respected computation lecturer:

  • “I don’t have an I.Q.”
    and(in the middle of a lecture):
    “What am I doing?”

An energetic lecturer:

  • “Note that one must always have his sleeves rolled up for discussing this kind of thing.”

Tautology-of-the-term prize:

  • “If you start off with a 72 elements and take away half, you’re left with the other half”


This file contains a list of quotes from people in mathematical or scientific circles at Cambridge.

NOTE: knowing some of my lecturers, this is very probably true! – SRV


Overheard at a supervision :

  • Supervisor: Do you think you understand the basic ideas of Quantum Mechanics ?
    Supervisee: Ah! Well,what do we mean by “to understand” in the context of Quantum Mechanics?
    Supervisor: You mean”No”,don’t you?
    Supervisee: Yes.

The Tautology prize goes to the lecturer who uttered the gem:

  • “If we complicate things they get less simple.”

This year’s modesty award is given for a phrase spoken by a lecturer after a rather difficult concept had just been introduced.

  • “You may feel that this is a little unclear but in fact I am lecturing it extremely well.”

Overheard at last year’s Archimedeans’ Garden Party :

  • “Quantum Mechanics is a lovely introduction to Hilbert Spaces !”

A Senior mathematician was asked which language he used for some of his computing. He replied that he used a very high level language: RESEARCH STUDENT


From an algebra lecture:

  • “A real gentleman never takes bases unless he really has to.”

From the same lecturer:

  • “This book fills a well needed gap in the literature.”

And another encouraging book review:

  • “This book is only for the serious enthusiast ; I haven’t read it myself.”

Two quotes from an electrical engineer (but former mathematician):

  • “…but the four-colour theorem was sufficiently true at the time.”
  • “The whole point of mathematics is to solve differential equations!”

And,as a contrast,a quote from a well known mathematician/physicist:

  • “Trying to solve [differential] equations is a youthful aberration that you will soon grow out of.”

While on the subject how about this fundamental law of physics heard in General Relativity this year:

  • “Nature abhors second order differential equations.”

A perplexing quote from a theoretical chemist:

  • “…but it might be a quasi-infinite set.”

What is a “quasi-infinite set? Answers on a strictly finite postcard, please.

This year’s Modesty Prize is awarded to the lecturer who said :

  • “Of course,this isn’t really the best way to do it.But seeing as you’re not quite as clever as I am – in fact none of you are anywhere near as clever as I am – we’ll do it this way.”

From the same lecturer :

  • “Now we’ll prove the theorem. In fact I’ll prove it all by myself.”

And from a particle physics course :

  • “This course will contain a lot of charm and beauty but very little truth.”

A comparison between the programming languages BCPL and BSPL :

  • “Like BCPL you can omit semicolons almost anywhere.”

At the beginning of a course it is important to reassure the audience about how straight-forward the course is and about how good the lectures are going to be. But what about this quote from the beginning of the Galois Theory course:

  • “This is going to be an adventure for you…and for me.”

Or this one from Statistical Physics:

  • “At the meeting in August I put my name down for this course becase I knew nothing about it.”

In the middle of the Stochastic Systems course the lecturer offered this piece of careers advice:

  • “If you haven’t enjoyed the material in the last few lectures then a career in chartered accountancy beckons.”

A lecturer of Linear Systems found the following on his board when he arrived one morning:

  • “Roses are red,
    Violets are blue,
    Greens’ functions are boring
    And so are Fourier transforms. “

An engineer actually gave an answer to the question of “quasi-infinite” sets:

  • “It’s one with more than ten elements.”

And they wonder why buildings fall over…


From a supervisor :

  • “Any theorem in Analysis can be fitted onto an arbitrarily small piece of paper if you are sufficiently obscure.”

No matter how elegant a course is there will always be occasions when a certain about of arithmetic is called for:

  • “I just want you to have a brief boggle at the belly-busting complexity of evaluating this.”

A lecturer recently started to use RUNES in his course! His justification:

  • “I need an immediately distinguishable character…so I’ll use something that no-one will recognise.”

From a Special Relativity lecture:

  • “…and you find you get masses of energy.”

It’s nice to see the general-purpose ‘nobbling constant’ making a welcome return to Cambridge lectures:

  • “This must be wrong by a factor that oughtn’t to be too different from unity.”

A flattering comment by a student for his GR supervisor:

  • “She’s the only person in DAMTP who’s a real person rather than an abstract machine for doing tripos questions. “

A worrying thought from the same student:

  • “Sex and drugs? They’re nothing compared with a good proof!”

A description of a lecturer:

  • “G—-‘s a maniacal pixie!!!”

A less polite description of a famous (and notorious) mathematician:

  • “I personally think he’s the greatest fraud since Cyril Burt!!” – any guesses ?

Renormalisation holds no fears for this lecturer of Plasma Physics:

  • “…and divergent integrals need really sleazy cutoffs.”

In the true style of Cambridge Maths Tripos we have the following:

  • “Proof of Thm. 6.2 is trivial from Thm. 6.9”

Can anybody guess the context in which the following is correct ?

  • “This theorem is obviously proved as 13 equals 15.”

Why do mathematicians insist on using words that already have another meaning?

  • “It is the complex case that is easier to deal with.”

And from various seminars in the King’s College Research Centre:

  • “…the non-uniqueness is exponentially small.”
  • “I’m not going to say exactly what I mean because I’m not absolutely certain myself.”
  • “It’s dangerous to name your children until you know how many you are going to have.”
  • “You don’t want to prove theorems that are false.”

And that last one wins the Sybil Fawlty Prize for “Stating the Bleeding Obvious”.

A slightly more honest version of “The student can easily see that…” :

  • “If you play around with your fingers for a while, you’ll see that’s true.”

Suggestions are welcome on the meaning of this:

  • “If it doesn’t happen at a corner, but at an edge, it nonetheless happens at a corner.”

– Eh ?

In a Complex Variables course a long, long, LONG time ago a lecturer wanted to swap the order of an integral and an infinite sum…

  • “To do this we use a special theorem…the theorem that says that secretly this is an applied maths course.”

I never name my lecturers but he’s now head of the Universities Grant Commission. And a lot of universities would like to swap him for an infinite sum.

From an Algebra III lecturer :

  • “If you want to prove it the simplest thing is to prove it.”

This year’s Honesty Prize goes to the natural sciences supervisor, who replied to a question with

  • “Don’t ask me. I’m not a mathmo.”

And from Oxford…

  • “This does have physical applications. In fact it’s all tied up with strings.”


Good heavens, do I see a lecturer actually noticing the existence of his audience!

  • “Was that clear enough? Put up your hand if that wasn’t clear enough. Ah, I thought not.”

Snobbery or what?

  • “In the sort of parrot-like way you use to teach stats to biologists, this is expected minus observed.”
  • “I too would like to know what a statistician actually does.”
  • “We’re not doing mathematics; this is statistics.”

Also from statistics:

  • “You could define the subspace topology this way, if you were sufficiently malicious.”
  • “You mustn’t be too rigid when doing Fluid mechanics.”

Talk about ulterior motives…

  • “This handout is not produced for your erudition but merely so I can practice the TeX word-processor.”

From 1A NatSci “Cells” course:

  • “There are two proteins involved in DNA synthasis, they are called DNAsynthase 1 and DNAsynthase 3”

From a Part 2 Quantum Mechanics lecture:

  • “Just because they are called ‘forbidden’ transitions does not mean that they are forbidden. They are less allowed than allowed transitions, if you see what I mean.”

From an IBM Assembler lecture:

  • “If you find bear droppings around your tent, it’s fairly likely that there are bears in the area.”

A Biochemistry paper included an analysis of a previously undiscovered sugar named by the researchers “godnose” .

From a 1B Electrical Engineering lecture:

  • “This isn’t true in practice – what we’ve missed out is Stradivarius’s constant.”

And then the aside:

  • “For those of you who don’t know, that’s been called by others the fiddle factor…”

One from a 1A Engineering maths lecture :

  • “Graphs of higher degree polynomials have this habit of doing unwanted wiggly things.”
  • “Apart from the extra line that’s a one line proof.”
  • “This is a one line proof…if we start sufficiently far to the left.”

A slight difficulty occured with geometry in an Engineering lecture one day:

  • “This is the maximum power triangle.” said a lecturer, pointing to a rectangle.

This year the Computer Scientists seem to be in the running for the Honesty Award:

  • “Sorry, I should have made that completely clear. This is a shambles.”

From a Computer Sciences Protection lecture:

  • “Who should be going to this lecture? Everyone…apart from the third year of the two-year CompSci course.”
  • “I don’t want to go into this in detail, but I would like to illustrate some of the tedium.”

Oh those poor CompScis….

  • “I’m not going to get anything more useful done in this lecture, so I might as well talk.”
    later followed by …
    “Well there you are, one lecture with no useful content.”

Three from a NatSci Physics lecturer:

  • “You don’t have to copy that down — there’s no wisdom in it — it only repeats what I said. “
  • “We now wish to show that they are not merely equal but _the same thing_.”
  • “And before I leave this subject, I would like to tell you something interesting.”

From a first year chemistry lecture some personal problems of the lecturer:

  • “Before I started this morning’s lecture I was going to tell you about my third divorce but on reflection I thought I’d better tell my wife first.”

From a single research seminar at the King’s College Research Centre:

  • “I’m sure it’s right whether it’s valid or not.”
  • “WARNING: There is no reason to believe this will work.”