And lead weights to your feet may my words be,
that you move slowly, like a weary man,
to the ‘yes’ and ‘no’ of what you do not see.
For he is a fool, and low among his kind,
who answers yea or nay without reflection,
nor does it matter on which road he runs blind.
Opinions too soon formed often deflect
man’s thinking from the truth into gross error,
in which his pride then binds his intellect.
 
[E questo ti sia sempre piombo a’ piedi,
per farti mover lento com’ uom lasso
e al sì e al no che tu non vedi:
ché quelli è tra li stolti bene a basso,
che sanza distinzione afferma e nega
ne l’un così come ne l’altro passo;
perch’ elli ’ncontra che più volte piega
l’oppinïon corrente in falsa parte,
e poi l’affetto l’intelletto lega.]

Dante Alighieri (1265-1321) Italian poet

The Divine Comedy [Divina Commedia], Book 3 “Paradiso,” Canto 13, l. 112ff (13.112-121) [Thomas Aquinas] (1320) [tr. Ciardi (1970)]
    (Source)

(Source (Italian)). Alternate translations:

Now learn, my Son,
With tardy foot to make your Judgment run,:
And Fancy's wild excursions to repel
Unhappy they, who, by her lure betray'd.
And, like 'lorn travellers, by meteors led.
Their affirmation or denial give
Unweigh'd, for Fancy leans to Falsehood's part,
And soon to Passion's rule betrays the heart.
And her embruted Slaves in bondage live.
[tr. Boyd (1802), st. 19-20]

And let this
Henceforth be led unto thy feet, to make
Thee slow in motion, as a weary man,
Both to the ‘yea’ and to the ‘nay’ thou seest not.
For he among the fools is down full low,
Whose affirmation, or denial, is
Without distinction, in each case alike
Since it befalls, that in most instances
Current opinion leads to false: and then
Affection bends the judgment to her ply.
[tr. Cary (1814)]

Let this henceforth be lead unto thy feet,
To make thee move slow, like a weary man,
Both to the Yea and Nay, as far 's you can:
For he among the fools is low enough,
Without distinction, who affirms, denies,
Where one and where the other question lies.
It happens, too, that oftentimes incline
Opinions current to the falser side,
And intellect is by affection tied.
[tr. Bannerman (1850)]

And lead shall this be always to thy feet,
To make thee, like a weary man, move slowly
Both to the Yes and No thou seest not;
For very low among the fools is he
Who affirms without distinction, or denies,
As well in one as in the other case;
Because it happens that full often bends
Current opinion in the false direction,
And then the feelings bind the intellect.
[tr. Longfellow (1867)]

And let this be always as lead to thy feet, to make thee move slow as a weary man both to the yes and to the no that thou seest not; for he is very low down among the fools who affirms or denies without distinction, in the one no less than in the other pass: since it occurs that oftentimes the current opinion swerves in a false direction, and afterwards the desire binds the understanding.
[tr. Butler (1885)]

And let this to thy feet a dead weight be,
Like one fatigued to make thee journey slow
Towards the Yes, or No, thou dost not see.
For he amongst the fools is very low,
Who without thought affirmeth, or denies,
Whether to one or other step he go;
Because it happens that too often flies
Public opinion into error's part.
And then its influence the intellect ties.
[tr. Minchin (1885)]

And let this be ever as lead to thy feet, to make thee move slow as a weary man, both to the YES and to the NO which thou seest not; for he is very low among the fools who affirms or denies without distinction, alike in the one and in the other case: because it happens, that oftentimes the current opinion bends in false direction, and then the inclination binds the understanding.
[tr. Norton (1892)]

And let this ever be lead to thy feet, to make The thee move slow, like a weary man ; both to the yea and nay thou seest not;
for he is right low down amongst the fools who maketh affirmation or negation without distinction between case and case;
wherefore it chanceth many times swift-formed rash opinion leaneth the wrong way, and then con-ceit bindeth the intellect.
[tr. Wicksteed (1899)]

And let this always be lead on thy feet to make thee slow, like a weary man, in moving either to the yea or the nay where thou dost not see clearly; for he ranks very low among the fools, in the one case as in the other, who affirms or denies without distinguishing, since it often happens that a hasty opinion inclines to the wrong side and then the feelings bind the intellect.
[tr. Sinclair (1939)]

Ever let this, like lead, thy feed down-weigh
To make thee, where thou see'st not clear, move slow,
Like one who is weary, both to Yea and Nay.
For he among the foolish stands right low
Who affirms without distinction or denies
With whichsoever case he hast o do;
Since often it haps that rashness of surmise
Leadeth the judgment on false roads to start;
Then fond desire the understanding ties.
[tr. Binyon (1943)]

And to thy feet be this hobble, wrought
Of lead, to make thee move at sluggard pace
Toward Yea and Nay where thou perceivest naught,
For low among the dunces is his place
Who hastes to accept or reject
With no distinction made 'twixt case and case;
Thence come rash judgements, mostly incorrect
And prejudiced, and stubborn all the more
That self-conceit shackles the intellect.
[tr. Sayers/Reynolds (1962)]

And let this ever be as lead to your feet, to make you slow, like a weary man, in moving either to the yes or the no which you see not; for he is right low down among the fools, alike in the one asnd in the other case, who affirms or denies without distinguishing; because it happens that oftentimes hasty opinion inclines to the wrong side, and then fondness for it binds the intellect.
[tr. Singleton (1975)]

And let this always make your feet like lead
So that you move like a man who is worn out
Towards a Yes or No you cannot actually see:
For a man is right down among the fools
In the case either of affirmation or denial,
If he proceeds without making distinctions;
Because it often happens that a quick opinion
Inclines int he wrong direction, and after that
The intellect is hampered by vanity.
[tr. Sisson (1981)]

And let this weigh as lead to slow your steps,
to make you move as would a weary man
to yes or no when you do not see clearly:
whether he would affirm or would deny,
he who decides without distinguishing
must be among the most obtuse of men;
opinion -- hasty -- often can incline
to the wrong side, and then affection for
one’s own opinion binds, confines the mind.
[tr. Mandelbaum (1984)]

Let this be leaden weight upon your feet
to make you move slow as a weary man
both to the ‘yes’ or ‘no’ you do not see,
for he ranks low, indeed, among the fools,
who rushes to affirm or to deny,
no matter which, without distinguishing.
Opinions formed in haste will oftentimes
lead in a wrong direction, and man’s pride
then intervenes to bind his intellect.
[tr. Musa (1984)]

And let this ever be lead upon your feet, to make you move slowly, like a weary man, to both the yes and the no that you do not see:
for surely he is low among the fools who affirms and denies without distinction in either case,
for it often happens that a hasty opinion turns in a wrong direction, and then affect binds the intellect.
[tr. Durling (2011)]

And let this always weight your feet down with lead, and make you go slowly, like a tired man, approaching the yes or no you do not grasp, since he is truly down there among the fools, who affirms or denies without distinguishing between cases, so that it often happens that a quick opinion leans to the wrong side, and then Pride entangles the intellect.
[tr. Kline (2002)]

And let this be a lead weight on your feet,
so that you move as slow as if worn out
to any “yes” or “no” unclear to you.
For no fool is as low a fool as one
who taking either of these steps will fail
affirming to denying in distinction.
So often when our judgement rushes on
it happens that we veer in false directions
and then emotions bind tie intellect.
[tr. Kirkpatrick (2007)]

And let this always be as lead upon your feet
to make you slow, just like a weary man, in moving,
whether to yes or no, unless you see both clearly.
For he ranks low among the fools
who, without making clear distinctions,
affirms or denies in one case or another,
since it often happens that a hasty opinion
inclines one to the erring side, and then
fondness for it fetters the working of the mind.
[tr. Hollander/Hollander (2007)]

And let this forever be like lead on your feet,
Forcing you to go slowly, like someone weary,
Saying 'yes' or 'no' when neither is clear.
A man who either concurs or disagrees
Without some plain distinctions is a fallen fool,
And pretty low even at that level,
For hasty judgment often bends to what's wrong,
And having made a foolish choice the fool
Holds on, letting his foolery tie up his mind.
[tr. Raffel (2010)]