I think I have an idea about what is going on here. If I'm right, this puzzle is tough and I will need some help, so this answer is a community wiki.
I think ...
... the puzzle hast two parts. The top part has 14 clues. The answers to these clues are words of four to eight letters. The left hand side of the equation gives the statistics to the word counts: There are two 4-letter words, six 5-letter words, two 6-letter words, three 7-letter words and one 8-letter word.
The bottom part is the quote of the Argentine that we're looking for. I think the all answers of the top part are enumerated and 1 in the sum means the first letter of the first word and 79 means the last letter of the last word.
Why is this hard?
We don't know the enumeration, so we cannot cross-solve both parts as we can with some acrostics, or we can only cross solve them with solved clues at the end or at the beginning.
Time to chop the end up.
EPOCH (5) — time; anagram of CHOP + E (thE end) with cop doing double duty
I gave my heart for this.
TRICK (5) — cryptic definition, perhaps heart is a playing card?
Take something from this endless first mate.
THIEVE (6) — take something; THI (this endless) + EVE (first mate, according to Genesis)
The way to travel if you're late.
HEARSE (6) — cryptic definition, "late" meaning "dead"
Information from a legless duck.
LOWDOWN (7) — cryptic def., a duck without legs has low down.
Attacker eaten by a sith lord.
INVADER (7) — attacker; IN (eaten by) + VADER (a sith lord)
A little after the editor of the stream goes back to the future.
DESTINY (7) — future; TINY (little) after SED (Unix stream editor) backwards
Describes the spice that is found in a little fish.
FIERY (5) — describes the spice; IE (that is) in FRY (little fish)
Broken like an amphibian in the present.
TODAY (5) — in the present; anagram of TOADY (like an amphibian)
Raising the icon I had caught a spanish wave with an effort.
IDOLATRY (8) — raising the icon; ID (I had; I'd) + OLA (Spanish word for wave) + TRY (an effort)
The young cat lost time and direction and found a bird.
KITE (4) — bird; KITTEN minus T (time) and N (direction)
Feel half smooth.
IRON (4) — smooth; with the chemical symbol Fe (FEEL half)
They end by the way used by brewers and bakers.
YEAST (5) — used by brewers and bakers; Y (end of theY) + EAST (by the way? Hmmm.)
The poorest railway has a way to go.
TRAIL (5) — way to go; hidden in pooresT RAILway.
Filled-in parts of the quote
W O R D P L A Y H I
25 3 47 55 2 23 77 43 12 30
D E S A K E Y T O R
51 38 73 33 62 1 53 6 68 60
E A L I T Y T H A T
18 52 57 66 11 48 64 17 72 49
T H E D I C T I O N
59 5 22 37 41 9 40 63 27 42
A R Y T R I E S I N
58 76 70 74 20 45 71 21 54 69
V A I N T O L O C K
32 19 78 31 75 50 79 24 4 10
I N S I D E E V E R
13 29 39 8 34 14 65 15 35 67
Y F R E E W O R D
61 44 36 16 46 28 56 7 26
"Wordplay hides a key to reality
that the dictionary tries in vain
to lock inside every free word."
— Julio Cortázar