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Volume 6427
John Coleman Burroughs: Back to the Stone Age - 7 b/w plates
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Seven Worlds to Conquer
by Jess Terrell
An ERBapa Reprint


The Objective of this paper is to identify the “Seven Worlds to Conquer
by applying the Hierarchy of Needs, a psychology theory developed by Abraham H. Maslow.
The Argosy magazine version of “Back to the Stone Age” was entitled “Seven Worlds to Conquer
probably by a magazine editor and maybe without Burroughs approval.
This paper seeks to answer:  What were the “Seven Worlds to Conquer”?

The approach to this analysis is
1.)  Review the publishing history of “Back to the Stone Age”.
2.)  Establish Definitions.
3.)  Review the plot of “Back to the Stone Age”.
4.)  State the Theory of Worlds a.k.a. “the grand scheme”.
5.)  State the Theory of Lands Visited.
6.)  Present the Hierarchy of Needs.
7.)  Apply the Hierarchy of Needs to “Back to the Stone Age”

1.) BACKGROUND – Publishing History for “Back to the Stone Age”
Argosy: January 9, 1937- Seven Worlds to Conquer 1/6
Argosy Weekly January 9, 1937
“Seven Worlds to Conquer” by Edgar Rice Burroughs.
Cover by Emmett Watson.

 The question of the “Seven Worlds” has plagued yours truly since I became aware of the original title for "Back to the Stone Age" (BSA), the fifth book in the Pellucidar series.

BSA was written in 1935 with the working title of “Back to the Stone Age, A Romance of the Inner World”.  It was first serialized as "Seven Worlds to Conquer" in Argosy Weekly, January 9—February 13 1937 then published by Edgar Rice Burroughs, Inc. in 1937 as “Back to the Stone Age”.

As noted previously the phrase “Seven Worlds” to Conquer” was devised, not by Burroughs, but by an editor at Argosy.  How the editor arrived at the phrase or if the phrase was accurate by any measure remains a mystery.    However this paper will demonstrate the phrase “Seven Worlds to Conquer” has meaning that can be found in a theory of psychology.


Before proceeding with the analysis we must first establish a common ground.

Oxford Dictionary defines “world” as
W1.0)  The earth, together with all of its countries and peoples e.g.  ‘it's a wonderful world’
W1.1)  All of the people and societies on the earth e.g. ‘the whole world hates a Monday’
W1.2) Denoting one of the most important people or things of their class e.g. ‘a world superstar’
W1.3)  Another planet like the earth e.g. ‘the possibility of life on other worlds’
W2.0) A particular region or group of countries e.g. ‘the English-speaking world’
W2.1) A particular period of history e.g. ‘the ancient world’
W2.2) A particular group of living things e.g. ‘the animal world’
W2.3)  All that relates to a particular sphere of activity e.g. ‘the news shocked the football world’
W2.4) One's life and activities e.g. ‘he was master of his world’
W3.0) Human and social interaction e.g. ‘he has almost completely withdrawn from the world’
W3.1) A stage of human life, either mortal or after death e.g. ‘in this world and the next’

Definition of  “world”:

L1.0)  Oxford Dictionary defines “land” as “a country or state”.

Definition of  “land”:

Based on definition W2.0 this paper considers “lands held by a tribe or group of people” as a world.  Therefore, David Innes’ Sari would be considered a world but also a land.  In the Pellucidar novels we often see the phrase “land of Sari” from the master wordsmith.

In this paper italics are used to denote verbiage stated in an email as well as excerpts from books.

“BSA” was established by Dr. Henry Hardy Heins to abbreviate  “Back to the Stone Age”.

“ERB” is a commonly used abbreviation for “Edgar Rice Burroughs”.  “Mister B” and “Burroughs” are also references to “Edgar Rice Burroughs”.

A chart summarizing elements of BSA includes chapter numbers, chapter titles, event locations and significant events appears on the last page of this paper.  The chapter numbers used in the chart and in this discussion are from the Ballantine paperback editions and may differ from other editions of BSA.

3.) BACKGROUND – Plot 

“Back to the Stone Age” tells the story of Wilhelm von Horst who arrived in Pellucidar with the O-220 expedition then was presumed lost before that airship returned to the surface world.  Von Horst falls in love with a local young lady, La-Ja, but his love is not returned.  He overcomes challenges e.g. killing a Tarag (sabor tooth tiger) and Zarith (T-Rex).  He escapes a Trodon nest. Encounters several tribes and does make friends notably the Tander (mammoth) “Old White”. Eventually La-Ja admits her love for von Horst then recommends him as chief of her tribe.  David Innes finds von Horst at the end of BSA and offers him a return to civilization which von Horst declines.

A summary of each BSA chapter is at the ERB summary project:

The full text of BSA is available at ERBZINE:

A prologue for BSA, developed for Argosy magazine, may be read at

4.) THEORY OF WORLDS – (ERB Universe) 

Lee Strong, author of “Untamed Pellucidar”, once posed the same question of “What are the Seven Worlds?”    From an email exchange with Lee Strong on January 17, 2018:

 I am sure that you know that Burroughs' editor chose "Seven Worlds to Conquer", not Mister B himself.  That said, I believe that you have correctly identified "the" seven as the editor saw them.  ….        Nowadays, we might say that Burroughs' Seven were Venus, Earth (including Pellucidar), the Moon, Mars, Phobos, Jupiter and Poloda. However, that is after the fact analysis.  To complicate things, the Polodan solar system includes 10 other planets and Mister B briefly referred to the "satellites of the suns of Orion."  We know that he intended to write more in the Polodan solar system and would have probably have taken his hero Tangor to the planet Tonos if he had been in better health.   Did he plan to visit the planets of Orion as well???

Based on Lee Strong’s comments the “Seven Worlds” would be
1.) Venus
2.) Earth including Pellucidar
3.) Moon
4.) Mars
5.) Phobos
6.) Jupiter
7.) Poloda

But there are additional worlds in the ERB-universe.  “Beyond the Farthest Star” laid the groundwork for many worlds and adventures in the Polodian system.  Lee Strong also pointed out a reference, by Ras Thavas, to life on Mercury a.k.a. Rasoom (see “Mastermind of Mars”).    Using world definition W2.0 each lost city in Africa could be considered its own world.  Therefore when counting worlds in all of ERB’s works we could easily exceed seven had Mr. Burroughs continued to write.

David Critchfield, author of “The Gilak’s Guide to Pellucidar” responded:
I don’t agree with Lee’s theory because Burroughs’ title for the story was BACK TO THE STONE AGE: A ROMANCE OF THE INNER WORLD. It was a magazine editor that probably came up with SEVEN WORLDS TO CONQUER without giving it much thought.

Therefore,  the phrase “Seven Worlds” applies only to “Back to the Stone Age” and not to a “Grand Scheme” encompassing the entire universe of ERB’s worlds as described in the “Theory of Worlds”.   Thus Barsoom, Poloda, and anything outside of Pellucidar will be excluded from consideration in this paper.

5.) THEORY OF LANDS VISITED – (Back to the Stone Age)

The January 2018 email from David Critchfield describes the “Theory of Lands Visited”:

I suppose one could take a literal meaning of the seven worlds as those lands that von Horst did conquer or escape from. In order:
1. Trodon’s nest
2. Forest of Death
3. The underground lair of the Gorbuses
4. Basti
5. Ja-ru (home of mammoth-men)
6. Bison-men
7. Lo-har
The list provided by Mr. Critchfield echoed my first thoughts by presenting the seven principle locations or lands visited in Back to the Stone Age.    But that doesn’t seem to be enough.

The Lands Visited theory omits significant accomplishments that transcended a geographic location.  To understand why people do what they do, we now turn to a theory from psychology.

6.) HIERARCHY OF NEEDS – (Explained)

Developed by psychologist Abraham H. Maslow in 1943, the original Hierarchy of Needs described five tiers or levels of growth and achievement that a person may strive for in life.  Maslow’s work is useful in explaining human motivation and behavior.  For example, when hungry or thirsty one seeks food and drink or when caught out in the elements one seeks shelter and security.  Satisfying the need for food and the need for shelter are the first two levels on the Hierarchy of Needs.

According to Maslow’s theory, human behavior is motivated by having to fulfill a need.

From Simply Psychology at
Maslow's [original] hierarchy of needs is a motivational theory in psychology comprising a five-level model of human needs, often depicted as hierarchical levels within a pyramid.
Maslow (1943, 1954) stated that people are motivated to achieve certain needs and that some needs take precedence over others. Our most basic need is for physical survival, and this will be the first thing that motivates our behavior. Once that level is fulfilled the next level up is what motivates us, and so on.
In the 1970’s researchers identified two more levels, Cognitive and Aesthetic.  In the 1990’s a Transcendence level was added to create an eight level diagram.  These are the levels with some examples as to how they are attained (*).
1. Biological and Physiological needs - air, food, drink, shelter, warmth, sex, sleep, etc.
2. Safety needs - protection from elements, security, order, law, limits, stability, etc.
3. Belongingness and Love needs - work group, family, affection, relationships, etc.
4. Esteem needs - self-esteem, achievement, mastery, independence, status, dominance, prestige, responsibility.
5. Cognitive needs - knowledge, meaning, etc.
6. Aesthetic needs - appreciation and search for beauty, balance, form, etc.
7. Self-Actualization needs - realize potential, self-fulfillment, seek personal growth.
8. Transcendence needs - helping others to achieve self actualization.

Only seven of the eight levels will be used in this discussion.  No evidence was presented in the book that von Horst had reached the eighth level (Transcendence) although he does show potential.   If a sequel was ever written for BSA it would be interesting to see his progress.

For more information on the original five level Hierarchy of Needs

For more information on the newer eight level Hierarchy of Needs:


As stated in a previous section, The Lands Visited theory omits some accomplishments that transcended a geographic location.   The noteworthy accomplishments include
• Adapting a primitive routine for day-to-day life.
• Defend and feed oneself in the primitive world.
• Winning the Head of a Tarag.
• Gaining the love of La-Ja .
• Training of Old White.
•  Freeing slaves.
• Gaining Friendship.
• Becoming the chief of La-Ja’s people in Lo-har.

It would be very easy in a violent world like Pellucidar without friends and surrounded by dangerous creatures to place yourself first above all others then skedaddle back to civilization at the earliest opportunity.  But instead von Horst does help others then elects to stay in Pellucidar.  Each of these accomplishments seems worthy of recognition.
This paper will use the Maslow Hierarchy of Needs, to gauge von Horst’s personal growth as he moves through the events in BSA.  Furthermore each level of the Hierarchy can be considered as a world conquered addressing the question of the “Seven Worlds to Conquer”.

7 – Level 1 - Biological / Physiological Needs - Adapt to a primitive world

Von Horst seems at home in Pellucidar as told in chapter 5, “Into Slavery”:

The ease with which von Horst adapted himself to the primitive life of his cave-men companions was a source of no little wonder even to himself. How long a time had elapsed since he left the outer crust, he could not know; but he was convinced that it could not have been more than a matter of months; yet in that time he had sloughed practically the entire veneer of civilization that it had taken generations to develop, and had slipped back perhaps a hundred thousand years until he stood upon a common footing with men of the old stone age. He hunted as they hunted, ate as they ate, and often found himself thinking in terms of the stone age.

In addition his escape from the Trodon nest is but one of many feats of survival.

With these accomplishments von Horst fulfills the physiological level on the Hierarchy of Needs.

7 – Level 2 - Safety Needs – Defend oneself in the primitive world

In Pellucidar, as in many of ERB’s worlds, it is kill or be killed and also eat or be eaten.   The ability to wield a weapon for defense or for food can make the difference in life or death.

Von Horst learned weaponry as described in chapter 5, “Into Slavery”:

Skruf was armed with a knife and a spear when they set out upon their journey; and as rapidly as he could find the materials and fashion them, Dangar had fabricated similar weapons for himself. With his help, von Horst finally achieved a spear; and shortly thereafter commenced to make a bow and arrows. But long before they were completed he insisted that they must kill their game with the primitive weapons they possessed because the report of the pistol would be certain to attract the attention of enemies to them. As they were going through a country in which Skruf assured them they might meet hunting and raiding parties from hostile tribes, both he and Dangar appreciated the wisdom of von Horst's suggestion; and thereafter the three lay in wait for their prey with stone-shod spears.

The ability to defend and fight gives von Horst security and safety on the second level of the Hierarchy of Needs.

7 – Level 3 – Belongingness and Love Needs – Part 1:  Friendship

A predominant theme in BSA is von Horst’s desire for friendship.  In the second chapter Burroughs describes him as a “social animal”.  Several times von Horst expresses a need for friendship as seen in these excerpts:

From Chapter 3, “The Only Hope”:
As soon as the effects of the poison should have worn off and Dangar was free from the bonds of paralysis, he would have not only an active friend and companion but one who could guide him to a country where he might be assured of a friendly welcome and an opportunity to make a place for himself in this savage world, where, he was inclined to believe, he must spend the rest of his natural life. It was by far not this consideration alone that prompted him to remain with the Sarian but, rather, sentiments of loyalty and friendship.

From chapter 7, “Flight of the Slaves”:
There were no good-byes. A group or an individual walked out of the lives of those others with whom they had suffered long imprisonment, with whom they had fought and won to freedom; and there was no sign of regret at parting—just the knowledge that when next they met, they would meet as mortal enemies, each eager to slay the other. This was true of most of them, but not of all. There was a real friendship existing between von Horst and Dangar, and something that approached it between these two and Thorek. Where La-ja stood, who might know? She was very aloof. Perhaps because she was the daughter of a chief; perhaps because she was a very beautiful young woman whose pride had been hurt, or who was nursing a knowledge that her woman’s intuition had vouchsafed her, or because she was by nature reserved. Whatever her reason, she kept her own counsel.

From chapter 9, “The Charnel Caves
“You like me a little better, La-ja?” he asked. He was starved for friendship—for even the friendship of this savage little girl of the stone age.
“No,” said La-ja, emphatically. “I do not like you at all, but I know a brave man when I see one.”
“Why don’t you like me, La-ja?” he asked a little wistfully. “I like you. I like you—a lot.” He hesitated. How much did he like her?
"I don’t like you because you are sick in the head, for one thing; for another, you are not of my tribe; furthermore, you try to order me around as though I belonged to you.”
“I’m sure sick in the head now,” he admitted; “but that doesn’t affect my good disposition or my other sterling qualities, and I can’t help not being a member of your tribe. You can’t hold that against me. It was just a mistake on the part of my father and mother in not having been born in Pellucidar; and really you can’t blame them for that, especially when you consider that they never even heard of the place. And, La-ja, as for ordering you around; I never do it except for your own good.”
“And I don’t like the way you talk sometimes, with a silent laugh behind your words. I know that you are laughing at me—making fun of me because you think that the world you came from is so much better than Pellucidar—that its people have more brains.”
“Don’t you think that you will ever learn to like me?” he asked, quite solemn now.
“No,” she said; “you will be dead before I could have time.”

From chapter 13, “Captured”:
“Perhaps Thorek was your friend; but no other mammoth-man will be. Friendship for a stranger is weakness in a warrior. Strangers are to be killed; that is why they are strangers. If there were no strangers there would be no one to kill except one another, and that would not be good for the tribe. We would soon kill. each other off. Men must fight and kill; it is the life of warriors.”
Thorek confirms friendship with von Horst in chapter 14, “He Dies!
Thorek!” exclaimed von Horst.
“Well! Well!” roared [Thorek] the mammoth-man. “It is Von or I’m a jalok. So this is the man who tossed Trog and Gorph around? I am not surprised. I can toss either of them, and he tossed me.”
“You know him?” demanded Mamth.
[Thorek]  “Know him? We are friends. Together we escaped from Basti, taking the slaves with us.”
“Friends!” exclaimed Mamth. “He is a stranger. Mammoth-men do not make friends of strangers.”
“I did, and he made a good friend,” retorted Thorek. “Because of that he should have the friendship of all mammoth-men. He is a great warrior, and should be allowed to live with us and take a mate from among our women; or he should be permitted to go his way unmolested.”

The importance of Old White is described in chapter 18, “Bison-Men
While he was there he saw Old White often. The great beast fed in a great patch of bamboo that grew beside the river only a short distance from the tree in which von Horst had constructed a rude shelter. Often, when not feeding, it came and stood beneath the tree that housed the man. Upon such occasions von Horst made it a point always to handle the beast and talk to it, for it offered him the only companionship that he had. After awhile he came to look forward to Old White’s return, and worry a little if he seemed gone over-long. It was a strange friendship, this between a man and a mammoth; and in it von Horst thought he recognized a parallel to the accidents that had resulted eons before in the beginning of the domestication of animals upon the outer crust.

This fitting tribute to the accomplishments of von Horst and the discovery of friendship appears on the last page of Back to the Stone Age.

The men of Lo-har camped with the men of Sari in friendship, and there was much palaver; and a great deal of food was eaten, and they slept twice in that one camp before breaking [camp].

Relationships are covered on the third level of the Hierarchy of Needs with belongingness and love.    Von Horst’s quest for love is addressed in the next accomplishment.

7 – Level 3 – Belongingness and Love needs – Part 2 - The love of La-Ja

While not specifically stated it could be that La-Ja’s interest in von Horst began with this Tarag accomplishment.   In the final chapter La-Ja admits her love, saying  "I have been yours almost from the first but you were too stupid to realize it."

La-Ja’s affection is reinforced in the fight with the Zarith in the Forest of Death. In chapter eight, von Horst stood his ground firing shots into the young T-Rex charging at him.  Later La-Ja tells him “you are a very brave man”.

The gaining of La-Ja’s love is an “aspect of life” worthy of inclusion on any list of events or accomplishments.   Without question winning the hand of any of Burroughs’ heroines is dreamt of by both ERB hero and ERB reader.

Considering Pellucidar is a tough place to find both friends and love these events are significant.  With the friendships gained and with the love of La-Ja, von Horst fulfills the third level of the Hierarchy of Needs for Belongingness and Love.

7 – Level 4 – Esteem Needs – Part 1 - Winning the head of a Tarag

In  chapter 4, “Skruf of Basti”, much emphasis is placed on the value of the head of a Tarag.

"I have chosen my mate," explained Skruf, "but she demanded the head of a tarag to prove that I am a brave man and a great hunter.”

Von Horst, with Dangar’s assistance, kills the Tarag.  But Skruf takes the credit and attempts to present La-Ja with the trophy.   Eventually the facts, corroborated by Dangar, are revealed to the men of Basti.   Soon after von Horst tells La-Ja the true story of the Tarag.

If anyone doubts the bravery or skill of von Horst when facing the Tarag he does it again, this time in front of witnesses in chapter 17,   “Little Canyon”.
The tarag charged, his lips stretched in a hideous snarl that bared his great saber teeth to the gums, his jaws distended. Roaring, he charged upon the puny man-thing. Once before had von Horst stopped the charge of a tarag with a stone tipped spear. That time he had accorded the palm to luck. It seemed incredible that such luck would hold again. Yet, had it been wholly luck? Skill and strength and iron nerve had been contributing factors in his victory. Would they hold again against this devil-faced demon?
As the tarag rose in its final spring, von Horst dropped to one knee and planted the butt of the spear firmly against the ground. He was very cool and deliberate, though he had to move with lightning speed. He held the point of the spear forward, aiming it at the broad white chest of the saber-tooth; then, as the beast struck, the man rolled to one side, leaping quickly to his feet.
The spear sank deep into the chest of the tarag, and with a hideous scream the beast rolled in the dust of the canyon floor. But it was up again in an instant seeking with ferocious growls and terrifying roars the author of its hurt. It turned its terrible eyes upon von Horst and tried to reach him; but the butt of the spear, sticking into the ground, drove the point farther into its body; and it stopped to claw at the offending object. Its roars, now, were deafening; but von Horst saw that it was reduced to nothing more menacing than noise

Two defeats of a Tarag earns esteem for von Horst at the fourth level on the Hierarchy of Needs.

7 – Level 4 – Esteem Needs – Part 2 - Freeing the slaves

In Basti, von Horst, La-Ja and others are held as slaves.   It is von Horst who organizes the slaves and leads them to freedom.
He begins with a call to action in chapter six, “La-Ja”.
"He killed three guards and drove the others off the ledge?" demanded one of the slaves, incredulously.
"Yes," said Dangar; "alone, he did it."
"He is a great warrior," said the slave, admiringly.
"You are right, Thorek," agreed another. "But La-ja is right, too; it is death for us now no matter what happens."
"Death but comes a little sooner; that is all," replied Thorek. "It is worth it to know that three of these eaters of men have been killed. I wish that I had done it."
"Are you going to wait up here until you starve to death or they come up and kill you?" demanded von Horst.
"What else is there to do?" demanded a slave from Amdar.
"There are nearly fifty of us," said von Horst. "It would be better to go down and fight for our lives than wait here to die of thirst or be killed like rats, if there were no other way; but I think there is."
"Your words are the words of a man," exclaimed Thorek. "I will go down with you and fight."
"What is the other way?" asked the man from Amdar.
"We have this ladder," explained von Horst, "and there are other ladders in the caves. By fastening some of them together we can reach the top of the cliff. We could be a long way off before the Bastians could overtake us, for they would have to go far down the gorge before they came to a place where they could climb out of it."
"He is right," said another slave.
"But they might overtake us," suggested another who was timid.
"Let them!" cried Thorek. "I am a mammoth man. Should I fear to fight with my enemies? Never. All my life I have fought them. It was for this that my mother bore me and my father trained me."
"We talk too much," said von Horst. "Talk will not save us. Let those who wish to, come with me; let the others remain here. Fetch the other ladders. See what you can find with which to fasten them together."

Turning captivity into freedom earns von Horst bonus esteem in the Hierarchy of Needs.

7 – Level 5 – Cognitive Needs - Training of Old White

According to the Oxford Dictionary, Self-Awareness is “Conscious knowledge of one's own character, feelings, motives, and desires.”

From Oxford, the definition of Cognition is “The mental action or process of acquiring knowledge and understanding through thought, experience, and the senses.”

Von Horst knew how he preferred to be treated.  Throughout all of BSA von Horst first seeks to do unto others as you would have them do unto you, even though in Pellucidar the Golden Rule may not always be practical.

In “Mammoth Men”, chapter 12, von Horst was moved when he first discovered Old White.
 To see one suffering thus filled him with compassion; and though his better judgment warned him against it, he could not resist the urge to approach more closely and investigate
Von Horst then removed the bamboo that was stuck in Old White’s hide. This act of kindness begins a classic relationship of man and beast.

Later when Old White is captured the Mammoth Men, who specialize in training mammoths, find Old White to be impossible in this excerpt from chapter 17, the Little Canyon:
Screaming with rage, [Old White]  raised the struggling warrior high above his head; then he dashed him heavily to the ground. The three warriors who had been assisting with his training urged their mounts in, but too late. Old White placed a great foot on the warrior and trampled him into the earth. Then he seized the warrior on the nearest mount and hurled him across the gorge, and all the while he trumpeted and bellowed. As he lunged for another of the warriors the two turned their mammoths and retreated; but Old White pursued them, dragging the heavy log after him. That was the end of the mighty captive's training. Mamth, disappointed and angry, ordered all from the gorge, the bars of the gate were replaced; and they rode back down the canyon toward the village.
"Will you ever be able to tame Old White?"  [Von Horst] asked.
Thorek shook his head. "Not unless Mamth is crazy," he replied, "will he ever risk another warrior on that brute. [Old White] is a natural killer. Such as he are never tamed. He has killed many warriors, and knowing how easy it is to kill us he would never be safe."
"What will become of him?"
"He will be destroyed, but not before he has afforded the tribe some entertainment." They rode on in silence.

Later, Old White rescues von Horst from the Mammoth Men in the same chapter setting up time for a bonding experience.

The success of surface dweller von Horst in taming Old White is a significant accomplishment made more so by the failure of the “expert” Mammoth Men.

Employing self-awareness and cognition to accomplish the un-do-able task  completes the cognitive level for the Hierarchy of Needs.

7 – Level 6 – Aesthetic Needs – The Beauty of Pellucidar

With danger at every turn and risk with every step, von Horst found the beauty that is Pellucidar as told in this excerpt from chapter 12, Mammoth Men,
Beyond the hills stretched another rolling plain through which wound a large river. He viewed it first from the summit of the pass that he had followed through the hills along an ancient trail worn deep by the feet of men and beasts through countless ages. There was a fringe of forest along the river and little patches of wood scattered about the plain which stretched away to his right to merge in the distance with what seemed the blue of an ocean. Ahead of him, far away, another forest bounded the plain upon that side, while to his left the hills curved around to meet the forest in the distance. Game dotted the landscape as far as the eye could reach. In the nearer foreground he could distinguish bos and red deer, antelopes, tapirs, sheep, and several species of herbivorous dinosaurs; while at the edge of the forest skirting the river he made out the huge forms of mammoths and giant sloths. It was a scene of such primitive beauty and interest that von Horst stood spellbound for several minutes, fascinated by its loveliness. For the moment he forgot everything but the scene below him;

Another example of von Horst being taken with his surroundings is chapter 18, Bison-Men,
As his eyes scanned the broad, horizonless vista that melted into a soft vignette at the uttermost range of human eye-sight it was difficult to reconcile the complete primitiveness of this untouched world with his knowledge that a bare five-hundred miles beneath his feet might be a city teeming with the traffic and the concerns of countless humans like himself who went their various ways and lived their lives confronted by no greater menace than a reckless driver or a banana peel thrown carelessly upon the pavement.
Each new rise of ground that he approached aroused his enthusiasm for the unknown. What lay beyond the summit?
What new scenes would be revealed? Thus once, as Old White moved ponderously up a slight acclivity, the man’s mind conjectured what might lie beyond the summit they were approaching, his anticipation of new scenes and his enthusiasm seemingly undiminished; then he heard a deep bellow, followed by others. Mingled with them seemed to be the voices of men.

To look past the danger and overcome the fear to find the beauty of Pellucidar awards von Horst the Asthetic level on the Hierarchy of Needs.

7 – Level 7 – Self-Actualization  - Part 1 –  Reject civilization to stay in Pellucidar

Von Horst turns down a trip back to the surface world, last chapter
"La-ja!" exclaimed the chief. "I had given her up for dead. I have searched a world for her."
"You will come back to Sari with us, Lieutenant?" asked Innes. "Gridley may come back on another expedition at any time now; it may be your only chance to return to the outer crust."
Von Horst glanced at a little, yellow haired cave-girl gnawing on a bone.
"I am not at all sure that I care to return to the outer crust," he said.

The decision to stay in Pellucidar puts von Horst on the road to fulfillment moving him closer to the Self-Actualization level.

7 – Level 7 – Self-Actualization  - Part 2 – Chief of Lo-Har

With La-Ja’s support von Horst becomes Chief of La-Ja's tribe in the last chapter.
Together they returned to the village of Lo-har. The warriors and the women clustered about.
"Where is Gaz?" they asked.
"Gaz is dead," said La-ja.
"Then we have no chief."
"Here is your chief," replied the girl, laying a hand upon von Horst's shoulder.
Some of the warriors laughed, others grumbled. "He is a stranger. What has he done that he should be chief?"
"When Brun went away, you let Gaz be chief because you were afraid of him. You hated him; and he was a poor chief, but none of you was brave enough to try to kill him, Von killed Gaz in a fair fight with knives, and he has taken the daughter of your chief as mate. Until Brun returns what warrior among you is better qualified to be chief than Von? If any thinks differently let him step forward and fight Von with his bare hands."
And so Lieutenant Frederich Wilhelm Eric von Mendeldorf und von Horst became chief of the cliff-dwellers of Lo-har. He was a wise chief, for he combined with the psychology of the cave man, that he had acquired, all the valuable knowledge of another environment. He became almost a god to them, so that they no longer regretted the loss of Brun.

To achieve one’s full potential as a leader of people places von Horst at the Self-Actualization level on the Hierarchy of Needs.


The in-depth examination of von Horst’s accomplishments in this paper has demonstrated his growth as an individual through each of the seven levels described in the Hierarchy of Needs.
This paper also illustrates that each of the seven levels from the Hierarchy of Needs can be considered as a world in the title, “Seven Worlds to Conquer”.


There is no intention in this research or in this paper to imply or suggest that Burroughs used the Hierarchy of Needs in developing Back to the Stone Age.  But this paper does illustrate the personal growth of the hero, von Horst and makes BSA more than just another trip to Pellucidar.
The intent is to show that the “Seven Worlds to conquer” are analogous to the seven levels of the Hierarchy of Needs.

Back to the Stone Age
Von Horst with spear in hand versus a mammoth by Frank Frazetta.
This painting used as cover for Ace paperback, first issued in 1973.


Argosy Weekly January 9, 1937  Cover by Emmett Watson.
• The Eight-stage Hierarchy of Needs at
• “Back to the Stone Age” Dust Jacket by John Coleman Burroughs.
• Von Horst versus a mammoth by Frank Frazetta.  Used as cover for Ace paperback, issued 1973.
• Chart listing chapter, location, and event by Jess Terrell.
• The 1963 Ace paperback and Artwork by Roy Krenkel assisted by  Frank Frazetta.
• The  1973 Ace with cover by Frank Frazetta.
• The  1990  Ballantine with cover by David B. Mattingly.

Pictures and images are courtesy of Back to the Stone Age
Charts by Jess Terrell


Definition of  “world”:
Definition of  “land”:
Definition of  "self-awareness":
Definition of  "cognition":
A summary of each BSA chapter:
The full text of BSA:
Prologue for BSA, developed for Argosy magazine:
For more information on the original five level Hierarchy of Needs:
For more information on the newer eight level Hierarchy of Needs:

Roy Krenkel ACE coverFrank Frazetta ACE coverDavid B. Mattingly Ballantine cover
 Left the 1963 Ace paperback and Artwork by Roy Krenkel assisted by  Frank Frazetta
 Center 1973 Ace with cover by Frank Frazetta; Right Ballantine by David Mattingly


1. At the Earth's Core
2. Pellucidar
3. Tanar of Pellucidar
4. Tarzan at the Earth's Core
5. Back to the Stone Age
6. Land of Terror
7. Savage Pellucidar

Tarzan Untamed Core Values
Moon Maid Glossary Update
Evil Queens Anonymous
Sleepover at Opar

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