John Locke's Idiots and Madmen

I don’t usually toss around invectives about others as a matter of routine, but in this blog post I’ll need to use the word “idiot,” and the discussion will make more sense if I define it.

It’s derived from the Greek word meaning a “person lacking professional skill,” or “private person”; or late Latin, “uneducated or ignorant person.” The “private” part of the definition is not the solitary individualist, but it refers to a person who is oblivious of the consequences his or her actions may have upon others.

Idiots and Madmen

John Locke (1632–1704) also wrote about idiots, and he makes a distinction between idiots and madmen. Locke, if you’ve never studied him, was regarded as one of the most influential of Enlightenment thinkers and commonly known as the "Father of Liberalism.” In addition to what I’m about to discuss, he has relevance to all Americans because he had a huge influence on the American revolutionaries and our constitution, especially his ideas about religious tolerance, the right to own property, and political theory. The phrase, “life, liberty, and pursuit of happiness” in the Declaration of Independence, can be traced to Locke’s theory of rights.

His arguments concerning liberty and the social contract later influenced the written works of Alexander Hamilton, James Madison, and especially Thomas Jefferson, and other Founding Fathers of the United States. In fact, one passage from Locke’s Second Treatise on Government is reproduced verbatim in the Declaration of Independence: the reference to a “long train of abuses.” Such was Locke’s influence that Thomas Jefferson wrote: “Bacon, Locke and Newton... I consider them as the three greatest men that have ever lived, without any exception, and as having laid the foundation of those superstructures which have been raised in the Physical and Moral sciences.”

But today I’m interested in what he says about idiots and madmen in his Essay Concerning Humane Understanding (1690). Locke writes this about idiots: “the defect …seems to proceed from want of quickness, activity, and motion in the intellectual faculties, whereby they are deprived of reason…”

But madmen are different:

…madmen, on the other side, seem to suffer by the other extreme. For they do not appear to me to have lost the faculty of reasoning, but having joined together some ideas very wrongly, they mistake them for truths; and they err as men do that argue right from wrong principles. For, by the violence of their imaginations, having taken their fancies for realities, they make right deductions from them.

He’s really discussing the way people think, or more precisely, aren’t thinking well. He offers a succinct contrast between the two:

In short, herein seems to lie the difference between idiots and madmen: that madmen put wrong ideas together, and so make wrong propositions, but argue and reason right from them; but idiots make very few or no propositions, and reason scarce at all.

When Locke writes that madmen “argue and reason right from them,” (them = wrong ideas), he doesn’t mean their conclusions are correct; he means that they have reasoned logically from a wrong premise. A more modern way of saying this would be that although one can construct a logically valid argument from a false premise, the conclusions will be wrong.

Using Locke’s definition, let’s look at a few of the ideas promoted by “madmen” (in Locke’s sense) of the guitar world. In this post, I’ll focus on writings about the use of the left hand.

The Left Hand

I’m going to leave out most of the history of the specious advice about keeping the left hand parallel to the side of the fingerboard at all times or the wacky idea that ignores basic tenets of geometry that the fingertips of each finger should each stop their notes perpendicular to the fingerboard, although I’ll necessarily mention these briefly below. I mainly want to discuss the use of the left hand when playing slurs and getting in and out of chords.


Here’s Julio Sagreras in 1933:

In playing descending slurs, the left hand finger that should press the most is not the finger that pulls the slur off, but rather the finger that remains holding the string down to the fretboard for the 2nd note which must remain firm enough to resist the sideways movement of the of the string as a result of the movement of the finger articulating the slur.

Why does the string even have to have a sideways movement that needs to be resisted? This is actually instruction to play with more tension than necessary.

What is a student to make of this remark by Frederick Noad writing about ascending slurs?

When hammering, each finger should come down vertically on its extreme tip. At first you will find this difficult with the 4th finger, but practice will quickly remedy this.

Students should note that there’s the difficulty that inheres in an advanced technique; there’s the difficulty of trying to acquire a skill for which one is not prepared; and there’s the difficulty that results from doing something that’s at odds with effective use of the body. Were I a student, I’d want Noad to explain why it’s difficult “with the 4th finger.”

A brief aside is required to explain why it’s more difficult: By positioning the inside of the palm parallel to the fingerboard and trying to have the fingertips fall perpendicularly on the strings—the “wrong” principles from which he’s reasoning—one loses the ability to activate the semi-independent metacarpal of the fourth finger because it’s placed at its limit of extension. The metacarpals are the bones in the palm of the hand (the carpal bones are in the wrist; the metacarpals are beyond them). The metacarpal for the fourth finger has range of movement of 20º. Go ahead and take your right hand, grab your left palm just beneath the fourth finger, and you’ll see you can wiggle the metacarpal back and forth. You can’t do that with the metacarpal for the index or middle fingers. The metacarpal for the annular (ring) finger has slightly less range of movement (10º–15º). Ascending slurs are not all that difficult if one positions the hand to take advantage of the strength and semi-independence of the metacarpal.[1]

Back to Noad: what kind of practice will remedy this difficulty? Noad doesn’t say. He just says “practice will remedy this.” Phrases such as these are usually uttered absent an ability to offer useful insights about how to work and why, which is a systemic problem in music instruction.[2] One might expect this in instruction geared to amateurs, but, sadly, it also exists in instruction offered to those who wish to become high-level players.

And what about this:

Are you playing right on the tips of the left hand fingers? If you are, they probably were uncomfortable for a week or two, but this should be wearing off now, and you will have formed a correct habit. This becomes more important as chords are introduced.

What’s the correct habit? This is more wishful thinking than it is actual instruction. It seems the false “principle” from which Noad is reasoning in this case is not a principle at all but is the directive to “keep the left-hand fingers perpendicular to the strings” masquerading as a principle. Our fingers are not parallel to each other when there is even the slightest space between them. When playing guitar, they have to be contorted to approach a plane (the guitar fingerboard) at the same angle, i.e., 90º, which is what perpendicular means.[3]

It was Matteo Carcassi who introduced the idea that ascending slurs are produced by the fingers moving like hammers: he writes “en forme de marteau.” Charles Duncan, in The Art of Classical Guitar Playing refers to this as “the swing of an axe.” This advice isn’t so bad if you know—and you would know if you’ve ever chopped wood—that once you initiate the movement, you let the axe fall. Duncan probably should have said, “the fall of an axe.”

But it’s in descending slurs where we have the most problems.

In 1933, Emilio Pujol defined the descending slur very specifically, and his definition has simply been accepted by many: “pull the string sideways with the same finger towards the string immediately above it in parallel direction to the plane of the strings and the frets. The motion of this finger should come to rest on the next string while stopping the second note of the slur.” (His use of the word “above” refers to the higher pitched adjacent string rather than higher in space.) This advice is probably responsible for the laboriously executed trills I hear in guitar auditions.

Pujol adds:

In playing descending slurs, the left hand finger that should press the most is not the finger that pulls the slur off, but rather the finger that remains holding the string down to the fretboard for the 2nd note which must remain firm enough to resist the sideways movement of the of the string as a result of the movement of the finger articulating the slur.

Charles Duncan says pretty much the same thing: “Flex the tip straight back so that it rests momentarily against the next higher string, and then relaxes away from the fingerboard.”

Pascal Roch and others maintain that when performing descending slurs, both fingers need to positioned ahead of time. You then, “draw back smartly the finger stopping it [the higher note] so the second note can sound.” He reiterates many times in his book that all the fingers involved in a descending slur should be placed simultaneously.

All this advice is given by those whom Locke would term “madmen.” They are reasoning, but they are reasoning from principles they have not defined, or those they have defined are faulty: parallel, preparation, counteracting force. As I mentioned above, the “principles” are usually directives in disguise.

Not one of these guitarists considers exactly where on the string the fingertip contacts the string. It will vary according to the type of slur. There’s no need to counteract pressure. If there is, one is using too much force, probably created because of the way the string is contacted.[4]

Where the fingertip contacts the string is important because it helps determine the path of the finger after performing the slur. If the hand can be positioned so that the fingertip can contact the string on its bass side, the trajectory of the finger performing the slur can be such that it needs neither to create “sideways movement of the string” nor “come to rest on the next string,” as advised by Pujol. Practicing slurs of double notes can help one learn to position the hand to ensure the fingertips can contact their strings more precisely. Thomas Tellefsen, a student of Chopin’s, reminds us that, “it is not the exercise, per se, that one practices, but the development of the hand by means of it.” And if one does wish a finger to come to rest against the higher adjacent string (however briefly) after a slur, one can contact the string more towards its treble side while performing the slur.


About chords Carcassi writes:

It is important that the fingers of the left hand are placed in position before striking the first note; at the same time the fingers of the right hand must be ready to pluck the notes of the chord. The left hand fingers should stay on the frets until the chord is completed.

Sherwood’s Guitar Method from 1902 says the same thing: “It is necessary before striking the strings that the fingers of the left hand be simultaneously placed on all the notes forming the chord. This is a fundamental rule.” He’s really just ripping off Carcassi, as did so many guitar methods from the late nineteenth and early twentieth-centuries.

Emilio Pujol writes a lot about this in 1933:

  • All the fingers which are used in a given position should be placed all the same time, at exactly the same time that the right hand plucks.
  • The string must be stopped by the left hand at exactly the instant in which it is struck by the right hand, and this means the actions of the two hands must correspond closely.
  • About an arpeggio study: “The change of position must be carried out by a simultaneous movement of all four fingers.”

But note that lutenist Jacques Gallot wrote in 1684: “Always position the [left-hand] fingers on the strings first which are to be played first, then place the others after.” He had it right. In high level playing, keeping some notes of a chord down while other fingers are choreographed to move to play the next thing is a sine qua non of legato playing. If one strictly follows Carcassi’s and Pujol’s advice, one’s playing will be halting and choppy. Additionally, one’s musicianship will be prevented from developing past a certain point.

There is an exception to Gallot’s advice, though. Because the index finger has an independent extensor muscle, it can reach down more and with greater ease than the fourth finger can reach up the neck of the guitar. This means that difficult reaches and chord shapes will be easier when fingers are placed in the order of the highest number finger to the lowest and large reaches taken with the index finger, even if this is sometimes at odds with order in which notes are to be sounded. There’s a discussion of this along with some exercises to explore this technical refinement on pages 143–148 of The Classical Guitar Companion.

  1. See pages 11–12 and 16 of Mastering Guitar Technique (Mel Bay). ↩︎

  2. See page of 105 of my Practicing Music by Design: Historic Virtuosi on Peak Performance (Routledge). ↩︎

  3. The left-hand fingers playing perpendicular to the strings is oft-repeated counsel. Aguado mentions this in his Nuevo Metoda para Guitarra from 1843: “The pupil must also take care to bend the fingers so that the last joint is perpendicular to the string.” However, he corrected this in an Appendix to his method that was in preparation at the time of his death in 1849: “In this case the other fingers will have to be placed obliquely to the frets instead of being nearly perpendicular, as I said in paragraphs 68 and 69 of the New Method.” ↩︎

  4. See pages 121–123 in The Classical Guitar Companion (Oxford) for more discussion and illustrations of this. ↩︎