As the first of Bacon's natural-historical treatises presents so much clear evidence of concord with the first drama of the Folio-Edition it impels one to turn to the second natural-historical section in order to examine whether such also contains threads of connection with some particular Shakespeare play.
The History of the Winds appeared in 1622. Five prefaces, also in Latin, representing five separate sections of natural history which were to appear in the five next following months, were appended thereto. The prefaces were those to The History of Dense and Rare (Historia Densi et Rari), to The History of Heavy and Light (Historia Gravis et Levis), to The History of the Sympathy and Antipathy of Things (Historia Sympathiae et Antipahiae), to The History of Sulphur, Mercury and Salt (Historia Sulphuris, Mercurii et Salis), and to The History of Life and Death (Historia Vitae et Mortis). But the intention was not carried into effect. The following months were productive of nothing. And when in the following year (1623) a second treatise appeared, it was not The History of Dense and Rare as originally intended, but that referred to in the sixth place, namely, The History of Life and Death.

As Bacon says on the first page of matter, he had decided to publish this in the second place owing to the extreme importance of the subject (secundum edere, propter eximiam rei utilitatem). And it really is with an extraordinary important fraction of the Shakespeare Folio-Edition of the same year that The History of Life and Death stands in intimate connection, namely with The Tragedie of Hamlet, Prince of Denmarke.

And in the same manner as The Tempest not only parabolises The History of the Winds but also stands in active thought connection with all other parts of The Great Instauration, so is it the case here. Hamlet mirrors not only the ideas set forth in The History of Life and Death; it is at the same time, even down to the details, a poetical elucidation of the fourth book of Bacon's Encyclopedy, De Augmentis Scientiarum. It presents close comparisons with The History of Dense and Rare (which appeared for the first time many years after Bacon's death), as well as with various parts of Sylva Sylvarum, with the parable Proserpina, or Spirit, with the two essays Of Death, with a list of separate sciences appended to The New Organon and with a page of manuscript from Bacon's large Memorandum-Book. The foregoing statement is reproduced in tabular form. The result of our examination will confirm the correctness of the following sketch.

The first act consists of five scenes. Three of them take place on the fortress-terrace, one is held in the hall of the castle and one in the dwelling room of the Lord Chamberlain, Polonius. This is how they are directed to be played in the modern editions. The Folio-Edition of 1623 leaves the place of action to the imagination of the reader.
In the silence of a bitterly cold, star-lit winter night Barnardo, Marcellus and Horatio await the apparition of the deceased king, which had already shown itself on the same spot in the preceding night. The spirit appears. They try to induce it to speak—in vain. They try to detain it—without success. It disappears as it came. The three decide upon telling Prince Hamlet what has happened.
In the second scene the Court is seen assembled in the castle hall. Gertrude, the widow of the deceased king, has married his brother, the actual king of the Danes, Claudius. Prince Hamlet is the only one who has not yet laid aside his mourning garb. His mother adjures him to throw off his sombre thoughts and garments. She and his step-father unite in begging him not to return to the Wittenberg High School, but to stay with them in Denmark. Hamlet consents, but as soon as the Court have left the stage he makes known in a soliloquy his longing for death and his disgust at a world in which his beloved mother could marry again within a month of the death of his cherished father. Horatio, Marcellus and Barnardo appear and tell the prince of he occurence of the night. It is arranged that they shall await the spirit on the terrace during the coming night.
In the third scene we see Laertes, the son of the Lord-Chamberlain, ready for a journey to attend the Paris University. He takes leave of his sister Ophelia and of his father Polonius. Ophelia gives him kindly advice and the father his blessing on the way. After Laertes has started Polonius warns his daughter against the love-triffling of Prince Hamlet.

The next scene shows us, again on a cold winter night, Hamlet accompanied by Horatio and Marcellus on the castle terrace. The spirit appears. But Hamlet cannot induce it to speak in the presence of the others. The spirit signs to him and Hamlet follows it in spite of the earnest dissuasive attempts of his friends. Arrived at another part of the terrace,the spirit calls upon Hamlet to execute vengeance. It tells him how, while sleeping in the orchard during the afternoon according to habit, he (the father) was murdered through the pouring of posion into his ear and that the murderer was his own brother, the present king. The spirit vanishes. The friends hasten to join Hamlet, who induces them to swear that, whatever may happen with regard to the occurence of the night, they will keep silence. This closes the first act.
We see that the dramatic kernel of this act is the spirit. During three and a half scenes it takes front rank with regard to the interest of the plot, whereas the first half of the second scene initiates us in all brevity into the state of matters in the royal family, while the third scene, in doing the same regard to the Polonius household, shows us a pleasant contrast to the sombre side. Quite two-thirds of the act are devoted to spirit.
But the spirit in Hamlet bears two names : Ghost and Spirit. Ghost is the personal name, whereas it is almost invariably referred to by the speakers as Spirit, and its statement begins with : I am thy Father's Spirit.
The word Spirit (in Latin Spiritus) also plays a great part in Bacon's scientific writings. The Spirit -theory, as will soon be briefly shown, is one of the principal points in Bacon's natural philosophy.This spirit-doctrine is based on the views held by the natural philosophers, Paracelsus, Telesius and Severinus Danus.
Theophrastus Paracelsus, the great Swiss thinker (he lived from 1493 to 1541), set up the theory; Bernardinus Telesius Consentinus, the Italian natural philosopher (1508-1588), enlarged upon it and Petrus Severinus Danus, the Danish physician (died in 1602), reduced it to a distinct system. Bacon understood no German, or, at most, very little thereof. He can scarcely have studied the intellectually rich and almost countless writings and pamphlets of Paracelsus as they were written in a style of German that was still clumsy and indistinct. But Bacon knew his theory from the principal work of Bernardinus Telesius of Cosenza, De Rerum Natura (Concerning the Nature of Things), of which the first two books appeared in 1565 and th whole was completed in 1586; he furthermore, knew this theory thanks to the work of the Dane Petrus Severinus : Idea Medicinae Philosohicae (The Idea of a Philosophical Medical System), which work was written in clear and lucid Latin and served him (Bacon) as instructor in the science of healing, the work being based on natural science. When Bacon, in quite early youth, began to sketch out the plan of his Great Instauration—and we find traces of this aim as far back even as before his fourteenth year—the works of Telesius and Severinus were the newest in the field of natural philosophy. Even Bacon himself, who very rarely mentions the names of other investigators, mentions the works above at short intervals in the 4th chapter of the 3rd Book of his Encyclopedy (The Theory of Theophrastus Paracelsus, eloquently reduced into a body and harmony by Serverinus the Dane; or that of Telesius of Consentium) and he mentions two of them again (Bernardinus Telesius and Paracelsus) in the 3rd Chapter of the 4th Book, wherein he discusses the question of the human soul in detail.
But, as we shall see soon, the Spirit in Hamlet is not a being created at will by poetical imagination but clearly the personification of the natural philosophical idea of the spirit according to Bacon's views. And thus the views of Paracelsus accord with those of Marcellus, while those of Bernardus Telesus harmonise with those of Barnardo in the first act of Hamlet. And Hamlet himself represents the ideas of the third in the trio, namely, of the physician Severinus Danus (anglice : the melancholy Dane). The time is out of ioynt and Hamlet is born to set it right! He, like Severinus Danus, deals with comparative anatomy.Like Severinus Danus he is enamoured of that healing art which is based on examination into natural laws.

Up to now no object of comparison has been shown to accord with the character of Horatio. But let it be considered that the word Horatio consists to the extent of five-sevenths of the Latin word ratio (reason, common sense). Horatio's first words,contained in his answer to Barnardo's question : Say, what is Horatio there? run : A peace of him. And ratio is, in fact, a piece of the word Horatio. Let it be noted further that Horatio is the one who doubts the longest of all, who continually allows common sense to argue, who, until the last moment, declares the appearance of the spirit to be a fantasy and addresses the spirit as an illusion, vouchsafing only a contemptuous it in so doing. Finally, let us consider the wonderful words of Hamlet to his friend Horatio in the third act :

Give me that man,
That is not Passions Slave,and I will weare him
In my hearts Core: I, in my Heart of heart,
As I do thee."

If all these points are well weighed we shall not go far wrong in accepting the Horatio of the tragedy as the representative of common-sense, or even as the embodiment of ratio itself. At least, during the continuation of the whole play the word Horatio whereever used in speech—and that is very often the case—may be throughly replaced by ratio. This always covers a fine double meaning.
Added to all this we shall find that in the first act of Hamlet two other natural-philosophers, Giordano Bruno and Patricius Venetus, are curiously alluded to and even that, in all probability, Francis Bacon himself plays a part therein.
The following assertions have thus been put forward with regard to the spirit-scenes of Hamlet, namely :

The spirit of Hamlet's father, and his name,
corresponding with the spirit as it is dealt with in Bacon's doctrine of the spirit.
The views of Marcellus, and his name,
according with those of Paracelsus
The views of Barnado, and his name,
corresponding with those of Bernardinus Telesius (in Italian Bernardino Telesio)
The views of Hamlet (the Dane), and his name,
corresponding with those of Severinus Danus (the melancholy Dane)
The views of Horatio, and his name,
corresponding with ratio (reason, common sense)
Giordano Bruno, Patricius Venetus and Francis Bacon play secondary parts.

Thus conceived, the material part of the first act,when considered from the scientific point of view, represents a dramatic illustration of the spirit-theory, personified by the spirit (ghost) of the deceased king and held in accord with the tenets of the most important natural philosopher of the 16th century.
In discussing the comedy of The Tempest, inductive reasoning was made the basis of argument. It is not so in this instance. For the sake of lucidiy the parabolism arising out of the spirit scenes is first dealt with in the present case. Starting from the poem let us proceed to the demonstration.
Let us first discuss the spirit! Bacon's spirit-theory is most clearly shown in the Rules (Canones) which form the conclusion of his History of Life and Death, in the Rules at the end of the History of Dense and Rare and in the chapter on the human soul , Book IV, Chapter 3 of De Augmentis Scientiarum. The chief principles laid down in all of these are, briefly summed up, as follows :
Every tangible body has one spirit, which is inanimate. Every living body has two spirits, the one inanimate, the other animate. Every human being has three spirits, the first inanimate, the second animate, and the third divine. Man has therefore firstly, a spirit such as is common to all bodies, that, concisely stated, is the spirit (spiritus); secondly, a spirit such as is common to all animals and which is variously called the spirit of life, animal soul, sensual soul, perceptible soul, or unreasoning soul; thirdly, a spirit peculiar to him, namely the actual soul, which is also called ther breath of life, reasoning soul, divine soul.
But the qualities of the intermediate, sensual soul which is common to both man and animal are most shortly and clearly described in the following passage in De Augmentis Scientiarum (IV,3). The wording thus : 

For the sensible soul— the soul of brutes— must clearly be regarded as a corporeal substance, atteneuated and made invisible by heat; a breath (I say) compounded of the natures of flame and air, having the softness of air to receive impressions, and the viguor of fire to propagate its action; nourished partly by oily and partlyby watery substances; clothed with the body, and in perfect animals residing chiefly in the head, running along the nerves, and refreshed and repaired by the spirituous blood of the arteries; as Bernardinus Telesius and his pupil Augustinus Donius have in part not altogether unprofitably maintained).

Shortly after this, we are told that this spirit is the principal soul in animals, whereas in human beings it is only the tool or instrument of the reasoning soul and therefore more deserving of the term spirit(spiritus) than of the name soul(anima).
We shall soon see that Hamlet recognises in his father's spirit both the divine soul (anima) and the animal soul (spiritus)
Our comparing the foregoing with the first act of Hamlet it becomes evident that the qualities of the Hamlet-spirit not only resemble those of the Bacon-spirit, but furthermore, that these qualities are presented to us in the Hamlet-scenes exactly in the same sequence as Bacon records them in the passage quoted above, namely : the first of such qualities in the first, the intermediate qualities in the second, and the last mentioned in the fourth and fifth scenes of Hamlet.
Bacon says : The sensual, or animal soul must be regarded as a corporeal substance. Thus, the spirit appears in the form of the deceased king. All these observers confirm it like the King that's dead—like the King—most like.
This corporeal substance is attenuated and made invisible by heat : consequently it is in no warm summer night that the spirit appears. The intense cold of the winter night is clearly indicated a the beginning of each scene wherein the spirit appears. Scene I, like Scene 4, begins with such like remarks as : 'Tis bitter cold— The Ayre bites shrewdly : it is very cold—It is nipping and an eager ayre. It is owing to the cold that the spirit is condensed and made visible.
The spirit substance is represented as being a breath compounded of the natures of flame and air, having the softness of air to receive impressions.—Hamlet.
Scene 1 :

Horatio. Stay, and speake. Stop it, Marcellus.
Marcellus. Shall I strike at it with my Partizan?
Horatio. Do, if it will not stand.
Barnardo. 'T is here.
Horatio. 'T is here.
Marcellus. 'T is gone. Exit Ghost

They strike at the venerable form of their king with their partisans! Do these gentlemen behave like officers? Methinks they act like natural philosophers. Hence comes it that Marcellus lets fall the words :

For it is as the Ayre, invulnerable.

And with the vigour of fire to propagate its action says Bacon further. The last Rule of the History of Life and Death morevoer says, in dealing more fully with the question : from flame the spirit gets its noble and powerful motions and activity. It's noble motions correspond exactly with that which Marcellus says immediately after the disappearance of the spirit :

We do it wrong, bring so Maiesticall
To offer it the shew of Violence

to which are forthwith added the above words

For it is as the Ayre, invulnerable.

—All this is contained in the first scene.—
The animal soul is clothed with the body and resides, in perfect animals, chiefly in the head.—This corresponds to a nicety with the longer remarks in the second scene :

Hamlet. Then saw you not his face?
Horatio. O yes, my Lord; he wore his Beaver up.
Hamlet. What, lookt he frowningly?
Horatio. A countenance more in sorrow than in anger.
Hamlet. Pale or red?
Horatio.Nay, very pale.
Hamlet. fixed his eyes upon you?
Horatio. Most constantly.

Let us take note that the scene, which the spectator has also experienced, is here again described in detail, and that partly from other points of view.
This, as already stated, occurs in the second scene.
The animal soul runs along the nerves and is refreshed and repaired by the spirituous blood of the arteries. In accord with this dictum, we find in the fourth scene, when Hamlet decides to follow the spirit, the words :

Hamlet. My fate cries out,
And makes each petty Artire in this body,
As hardy as the Nemian Lions nerve :

In human beings, says Bacon finally : dwell both animal soul (spiritus) and a reasoning, a divine soul (anima). And exactly thus is the question treated in the fourth and fifth scenes. The friends warn Hamlet not to follow the spirit for it might do him a harm.

Hamlet. Why, what should be the feare?
I doe not set my life at a pins fee;
And for my Soule, what can it doe to that?
Being a thing immortall as it selfe :

Here we hear of the immortall Soule (anima) existing in the spirit of the late king. But, when the spirit in the fifth scene has disappeared and calls up from below Sweare, Hamlet calls it boy—true penny—fellow—and old Mole. In this case the animal soul (spiritus) is addressed—as an animal. What, other than the natural philosophical view, could induce Hamlet, who has just spoken of it with veneration as father, king and immortal soul, to address it with so unflattering a name as old Moe?

Thus far, as has been seen, the words of the Encyclopedy and the first act of Hamlet are concurrent both in train of thought and in order of treatment.
A number of other expressions, moreover, confirm the fact that the spirit in Hamlet is a spirit in th sense of the natural-philosopher spirit-theory. Hamlet's first words to the spirit are :

Be thou a Spirit of health, or Goblin damn'd,
Bring with thee ayres from Heaven, or blasts from Hell.

Here again air and flame are found together as in Bacon's compounded of the nature's of flame and air. Mention is made of the noble motion not once but three times : with Martiall stalke—with sollemne march—with what courteous action. The spirit is for the day confin'd to fast in Fiers, in sulphurous and tormenting Flames. It is not allowed to wander by day; it is invisible through flame, exactly as the Baconian spirit is invisible by heat. Thus, the last Rule but one of the History of Life and Death accords on all three points with the spirit in Hamlet : Rule XXXI The living spirit perishes immediately, when it is deprived either of motion or of refrigeration or of aliment.) When, in the first scene, the spirit disapears, the three observers are about to take steps to deprive it of motion : Stay Illusion— Stay and speake— Shall I strike? Do, if it it will not stand. But, when it disappears in the fifth scene, it is the refrigeration together with aliment of which it is deprived, for the morning nears and the spirit fasts in fires by day and is therefore without nourishment.
It can only walk in the chill of the night. The approach of warmth causes it to think of departure :

But soft, methinks I sent the Mornings Ayre.

And shortly before vanishing it points, in true natural philosophical manner, by a comparison of the different light powers, to the approach of warmth and light:

The Glow-worme shoves the Matine to be neere
And gins to pale his uneffectuall Fire :

And, exactly as the spirit closes its speech with the simile of the glow worm, so ends Bacon his copius chapter on the spirit and soul of man by pointing to a branch of science, the Form of Light, which has not yet been sufficiently dealt with, wherein he recommends that investigation should be made as to what connection with fire and lighted matter have glow-worms and fire-flies.
It may be mentioned in passing that Bacon's parable relating to the spirit, which is contained in The Wisdom of the Ancients,(De Sapientia Veterum) namely Proserpina, or the Spirit, also presents a considerable number of striking points of comparison with the spirit in Hamlet. The spirit in Hamlet lives sometimes above and sometimes beneath the earth—just as is the case with Proserpina. The Hamlet spirit when beneath the earth is in the power of flame; Proserpina is in the power of the fire-god, Pluto. The Hamlet-spirit calls this abode its Prison-House; of Proserpina is said : she is enclosed and imprisoned beneath the earth)

In the Danish legend the senior Hamlet is cut down at a banquet; in the drama he is robbed of life while sleeping in his orchard. In exactly similiar manner Proserpina is carried off by Pluto while gathering flowers. Theseus and Pirithous endeavour to rescue Proserpina, but contrariwise are themselves curdled and never reascend again. In Hamlet Barnardo and Marcellus try to capture the spirit, while Horatio tells of their first encounter with the same and how they became almost to Jelly with the Act of feare. Taking into account the double meaning contained in never reascend again, the comparison between parable and drama may also be brought to show the same conclusion, inasmuch as Bernardo and Marcellus never reascend again—for after the close of the first act they never reappar on the stage. They are two figures that have naught to do except to help explain the spirit and its acts. On its final disappearance they likewise vanish from the stage. Besides the intimate similiarity of thought between the speeches in Hamlet, the passages in the Encyclopedy and the explanation contained in the parable of Proserpina, we find the jingling of names :

|Barnardo Theseus : Bernardo Telesius
Marcellus Pirithuous : Paracelsus

M and P, as lipped sounds, lie very near together. Morevover, it is desirable to take note of the philological fact that the names of all the three who observe the spirit have Italo-Latin endings; none of them have Scandanavian-Danish endings. Barnardo ends on an o just like the Italian name Bernardo; Marcellus with us, like the German-Latin Paracelsus; and Horatio more than coves the purely Latin word Ratio, including its Latin ending.
Let us now deal with the three above named characters more closely and from the scientific point-of-view! Here, once more,we find that it is Bacon's chapter on the human soul which furnishes the key to the matter. After enumerating the principal capacities of the soul, namely : Understanding, reason, imagination, memory, desire, will, and promising to handle them in the books of Logic and of Ethic, Bacon mentions two supplements to the science of the capacities of the soul, namely divination and fascination. Concerning divination, let us now read the following sentences (which are in the very same column as the words relating to the spirit of which mention is made above) :

The astrologer has his predictions,from the positions of the stars. The physician likewise has his predictions of approaching death, of recovery, of coming symptoms of diseases, from the urine, the pulse, the look of the patient, and the like. The politician also has his; O venal city, that will quickly perish, if it finds a purchaser : which prediction was not long in being verified; being fulfilled in Sylla first, and afterwards in Caesar. Predictions of this kind therefore are not to our present purpose, but are to be referred to their own arts.

And in the next column begins the explanation as to fascination, which is couched in the following terms :

Fascination is the power and act of imagination intensive upon the body of another(for the power of imagination upon the body of the imaginant I have spoken above); wherein the school of Paracelsus and the disciplines of pretended natual magic have been so intemperate, that they have exalted the power and apprehension of the imagination to be much one with the power of miracle-working faith. Others, that draw nearer to probability, looking for a clearer eye at the secret workings and impressions of things, the irradiations of the senses......)

The occurences in the first Hamlet scene, while the spirit is not on the stage, all correspond with the foregoing. Before it appears for the first time we hear from the mouth of Barnardo an astrological prophecy. The spirit vanishes and Horatio suggests that the apparition bodes some strange eruption to the state. After he has made a political prophecy which is exactly in accord with Bacon's writings, the spirit appears for the second time and, as soon as it has left the stage again, Marcellus speaks of the wonder working faith just in the sense of the Paracelsus-doctrine, to which Bacon makes reference.
That with such a mighty artist as the author of Hamlet all is interwoven into the play in the most pertinent manner, is natural. But, in spite of this, the passages which we have to discuss are not absolutely indispensible to dramatic effect. They are consequently often cut, or reduced to a minimum, under modern stage-management.
|Firstly, there is the astrological prediction from the position of the stars. Bernardo predicts, in accordance with his experience of the preceding nights and from the position of the stars, that the spirit will reappear at the same hour :

Barnardo. Last night of all,
When yond same Starre that's Westward from the Pole
Had made his course t'illume that part of Heaven
Where now it burnes, Marcellus and my self,
The Bell then beating one. (Enter the Ghost)

After the spirit has vanished again there follows the physician's prediction of an approaching sickness as indicated by the look of the patient. This time it is Horatio who is the prophet. The patient is the state. Horatio prophecies from the sorrowful eyes of his deceased king. He remarks :

Such was the very Armour he had on,
When th' Ambitions Norwey combatted :
So frown'd he once, when in an angry parle
He smot the sledded Pollax on the Ice.

and immediately thereupon follows the predicion :

In what particular thought to work, I know not:
But in the grosse and scope of my Opinion,
This boades some strange eruption to our State.

Upon this prophecy follow the longer narrative concerning the duel between the two kings and a description of the preparations that are being made for war by young Fortinbras of Norway. Then Horatio continues :

A mote it is to trouble the mind's eye.
In the most high and palmy state of Rome,
A little ere the mightiest Julius fell,
The graves stood tenantless, and the sheeted dead
Did squeak and gibber in the Roman streets :
As stars with trains of fire, and dews of blood:
Disasters inthe sun; and the moist star,
Upon whose influence Neptune's empire stands,
Was sick almost to doomsday with eclipse.

Not only do these words correspond with the political prediction to which Bacon makes reference in the third order; they have in two passages similarity with Bacon's words. Bacon speaks of the venal city that awaits a purhaser; in Hamlet it runs : the graves stood tenantless,—a term that is peculiarly commercial and legal. In Bacon it is Caesar, in Hamlet it is the mightiest Julius, a man towards whom Bacon at all times showed special inclination. Moreover, the last four lines and more particularly

.......and the moist star,
Upon whose influence Neptune's empire stands,
Was sick almost to doomsday with eclipse

contain many natural science-items.
The moon, the moist star of Neptune, to whose influence ebb and flood are due, was in eclipse and she is described as having been sick almos unto death.
The spirit appears a second time and, as soon as it has again vanished, words follow which correspond with the fourth passage in Bacon. These words are taken from the doctrine of Paracelsus, which places the power of imagination to be much one with the power of miracle-working faith. These issue from the mouth of Marcellus :

Marcellus. Some sayes, that ever 'gainst that Season comes
Wherein our Saviours Birth is celebrated,
The Bird of Dawning singeth all night long :
And then (they say) no Spirit can walke abroad,
The nights are wholesome, then no Planets strike,
No Faiery talkes, nor Witch hath power to Charme :
So hallow'd, and so gracious is the time.

Special note should be taken of the carefully-worded some sayes and the repetition thereof in brackets (they say)
Still more striking is the use of the words Fantasie and beleefe in the remarks of Marcellus which occur quite at the beginning of the scene :

Marcellus. Horatio saies, 'tis but our Fantasie,
And will not let beleefe take hold of him
Touching this dreaded sight, twice seen of us.

Others, so says Bacon , in opposition to the Paracelsus-doctrine, Others, that draw nearer to probability, looking with a clearer eye at the secret workings and impressions of things, the irradiations of the senses...........
The others corresponds to Horatio.
In answer to Marcellus he says sceptically : Tush, tush, 'twill not appeare. To the longer statemen concerning the belief in miracles, when the nights are wholesome he gives a cool reply, as if induced thereto by pure courtesy :

So I have heard, and do in part beleeve it.

and adds immediately that the morning comes and Let us impart what we have seene to night Unto young Hamlet.
We, however, find altogether five similarities of idea between Bacon's chapter on the human soul and the contents of the first Hamlet-scene, and all of these are in the same order of sequence, namely :

astromomical prophecy,
medical prophecy,
political prophecy,
the wondering view of the followers of Paracelsus,
the clearer view of Reason.

All these are used in the tragedy as explanatory interlocutions and while the spirit is not on the stage. Many other minutiae might be mentioned. For instance, the next sentence in Bacon runs :

(With this is joined the inquiry how to raise and fortify the imagination)

In the tragedy Marcellus and Barnardo try to raise and fortify the imagination of Horatio :

Marcellus. Horatio saies, 'tis but our Fantasie,
And will not let beleefe take hold of him.......
__________________________________
Barnardo. Sit down awhile
And let us once againe assile your eares,
That are so fortified against our Story........

Thus we have in Bacon the strengthening of the power of imagination whereas Horatio resists these powers, while the representatives of the power of imagination endeavour to storm and carry his fortification. Alliterative sense accompanies the alliterative sounds : fortificari—fortified.
But, whereas Barnardo and Macellus are ever ready to represent the side of the power of imagination, Horatio peristently combats the same by cautious doubts instigated by the better and cooler view of reason (ratio) :

Tush, tush, 'twill not appeare.

Only when he has seen the spirit with his own eyes and Barnardo confidently asks him :

Barnardo. How now Horatio? You tremble and look pale :
Is this not something more than Fantasie?
What thinke you on't?

—then only does Horatio answer, quite in the sense of the natural philosopher of sensuality and at the same time with a touch of juristical colouring :

Horatio. Before my God, I might not this beleeve
Without the sensible and true avouch
Of mine owne eyes.

To the question of Marcellus : Is it not like the King? Horatio answers with mathematical precision : As thou art to thy selfe. Again, when the spirit appears for the second time Horatio addresses it as illusion and only speaks of it, as were it only a thing and consequently neuter and directs Marcellus to strike at it with his partisan.
We gather from the second scene that Horatio has studied with Hamlet at Wittenberg. This is certainly a serious anachronism, for the historical Hamlet lived before the birth of Christ, whereas the University of Wittenberg was not founded until A.D. 1502 (by Frederick the Wise). It is probable that in the choice of the name of an university it was intended to hint at Giordano Bruno, the Italian natural philosopher, who had lived in London in the beginning of the ninth decade of the sixteenth century and afterwards taught at Wittenberg university, for his views also finds expression in Hamlet's and Horatio's words.
Again and again Horatio describes the spirit as an apparition and also assures the prince :

I knew your Father :
These hands are not more like.

Horatio has watched sharply and noted how the spirit fixed its eyes persistently on him and his fellow observers. Hamlet then asks : Staid it long?

Horatio. While one with moderate hast might tell a hundred.
All. Longer, longer.
Horatio. Not when I saw't.

Longer, longer, call out the two who are more readily influenced by imagination. Not when I saw't is the calm and positive assurance of Horatio, the clearest headed one of the three.
In the fourth scene Horatio warns the prince not to follow the spirit. It might assume another and horrible form :

Which might deprive your Souveraignty of Reason,
And draw you into madness think of it?

Hamlet frees himself and follows the spirit.

Horatio. He waxes desperate with imagination.

The two soul-qualities, Reason and Imagination, or Fantasie, are again found following close on one another, quite in the Baconian sense, while Horatio represents calmly testing and advising Reason (ratio).
After the impressive scene between the Spirit and Hamlet the friends seek for the prince. Illo,ho, ho—Hillo,ho,ho, they respectively call out in order to find each other in the darkness. In like manner Marcellus calls out Holla in the first scene and even by day-light, in the third act, Hamlet addresses his friends with : What hoa, Horotio! This Ho is a highly suspicious call when one considers that, on the other side, the remaining two-thirds of the name of Horatio play so important a part, viz. : Horatio.
And now let us note Horatio's last words in the first act. Even when the spirit calls out for the third time its subterranean sweare!, doubt is not removed from Horatio's mind :

Horatio. Oh day and night: but this is wondrous strange.

and Hamlet answers :

Hamlet. And therefore as a stranger give it welcome.
There are more things in Heaven and Earth, Horatio,
Then are dream't of in our Philosophy.

As we have seen, philosophy is, according to Bacon, the science of reason : There are more things in Heaven and Earth, oh Reason, than thy science can imagine!...................

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