perchance (adv.; archaic or poetic): possibly but not certainly; (synonyms): perhaps, probably, maybe, possibly, by chance, for all you know; (archaic): mayhap, peradventure, haply; [e.g.]: “Are we, perchance, overlooking one small detail?” ~ (Collins English Thesaurus).

perchance (adv.; archaic or poetic): possibly but not certainly; (synonyms): perhaps, probably, maybe, possibly, by chance, for all you know; (archaic): mayhap, peradventure, haply; [e.g.]: “Are we, perchance, overlooking one small detail?” ~ (Collins English Thesaurus).

• perfervid (adj.; literary): extremely ardent, enthusiastic, or zealous; (adv.): perfervidly; (n.): perfervidness, perfervidity, perfervour. [C19: from New Latin perfervidus, from Latin per-, (intensive) + fervidus, ‘fervid’, from fervēre, ‘to boil’]. ~ (Collins English Dictionary).

• perfervid (adj.): extremely or extravagantly eager; impassioned or zealous; (adv.): perfervidly; (n.): perfervidness. ~ (American Heritage Dictionary).

• perfervid (adj.): very fervent; extremely ardent; impassioned; (adv.): perfervidly; (n.): perfervidness. [1855-60, from Latin per-, intensive prefix + fervidus, glowing’]. ~ (Webster’s College Dictionary).

• perfervid (adj.): characterised by intense emotion; (synonyms): ardent, fervent, fervid, fiery, impassioned, torrid; [e.g.]: “Their secretive liaison soon blossomed into an ardent love affair”; “She is an ardent lover”; “He had a fervent desire to change society”; “She was a fervent admirer”; “His fiery oratory shook the auditorium”; “It was an impassioned appeal to the audience’s sensibilities”; “Their torrid love affair scandalised their social circle”; (related word): passionate (having or expressing strong emotions). ~ (Princeton’s WordNet 3.0).

• perfervid (adj.): 1. fired with intense feeling; (synonyms): ardent, blazing, burning, dithyrambic, fervent, fervid, fiery, flaming, glowing, heated, hot-blooded, impassioned, passionate, red-hot, scorching, torrid; 2. characterised by intense emotion and activity; (synonyms): burning, fevered, feverish, heated, hectic. ~ (American Heritage Roget’s Thesaurus; Expanded Version).

• perfervid (adj.): very fervid or hot; very ardent; [e.g.]: “Instruction, properly so called, they [the coloured preachers) are not qualified to give, but the emotional nature is aroused by perfervid appeals and realistic imagery”. (Fortnightly Recorder, Nova Scotia, XLIII. 861). [from Latin perfervidus, a false reading (though in form correct) for præfervidus, ‘very hot’, from Latin præ, ‘before’ (used intensively) + fervidus, ‘glowing’, ‘hot’, ‘burning’, ‘fiery’, ‘vehement’, from fervere, ‘boil’, ‘glow’; hence also (from Latin fervere) English fervid, fervour, ferment]. ~ (Century Dictionary and Cyclopaedia).

• perfervidness (n.): the character of being perfervid; extreme heat or ardour; great fervour or zeal. [= Spanish, Portuguese, Italian perficiente, from Latin perficien(t-)s, ppr. of perficere, ‘finish’, ‘complete’, ‘achieve’, from per, ‘through’ + facere, ‘do’]. ~ (Century Dictionary and Cyclopaedia).

• perfervid (adj.): very hot, very ardent (1830), as if from Latin *perfervidus, from per, ‘completely’ (see per) + fervidus, ‘glowing’, ‘burning’; ‘vehement’ (see fervid); related: perfervidly (adv.). ~ (Online Etymology Dictionary).

• per (prep.): through, by means of (1580s; earlier in various Latin and French phrases, in the latter often par), from Latin per, ‘through’, ‘during’, ‘by means of’, ‘on account of’, ‘as in’, from PIE root *per-, ‘forward’, hence ‘through’, ‘in front of’, ‘before’, ‘first’, ‘chief’, ‘toward’, ‘near’, ‘around’, ‘against’. ~ (Online Etymology Dictionary).

• fervid (adj.): burning, glowing, hot (1590s) from Latin fervidus, ‘glowing’, ‘burning’; ‘vehement’, ‘fervid’, from fervere, ‘to boil’, ‘glow’ (from PIE root *bhreu-, ‘to boil’, ‘bubble’, ‘effervesce’, ‘burn’); figurative sense of ‘impassioned’ is from 1650s; related: fervidly; fervidness. ~ (Online Etymology Dictionary).

• perpetual motion (n.): the hypothetical continuous operation of an isolated mechanical device or other closed system without a sustaining energy source. ~ (American Heritage Dictionary).

• perpetual motion (n.): 1. motion of a hypothetical mechanism which continues indefinitely without any external source of energy; it is impossible in practice because of friction; also called: perpetual motion of the first kind; 2. motion of a hypothetical mechanism which derives its energy from a source at a lower temperature; it is impossible in practice because of the second law of thermodynamics; also called: perpetual motion of the second kind. ~ (Collins English Dictionary).

• perpetual motion (n.): the motion of a theoretical mechanism that, without any losses due to friction or other forms of dissipation of energy, would continue to operate indefinitely at the same rate without any external energy being applied to it. [1585-95]. ~ (Webster’s College Dictionary).

• perpetual motion (n.): 1. motion which continues indefinitely without any external source of energy; impossible in practice because of friction; [e.g.]: “Oh ye seekers after perpetual motion, how many vain chimeras have you pursued? Go and take your place with the alchemists”. (p. 92, “Leonardo da Vinci Notebooks” (1494), Edward McCurdy; 1906, Duckworth & Co.); (related words): motion (a state of change; [e.g.]: “They were in a state of steady motion”). ~ (Princeton’s WordNet 3.0).

• perpetual motion (n.): 1. a machine which should do work without exhausting any power of doing work—that is, its work must not be accompanied by any displacement (such as the fall of a weight, or the uncoiling of a spring) or transformation (such as the combustion of fuel) which could not be undone by a replacement or counter-transformation without the expenditure of as much work as the machine has done. Such a machine is impossible, and contrary to all experience; for power of doing work is never increased nor diminished. Nevertheless, very many pretended perpetual motions have been put forth by deluded or knavish inventors. Most of them are of two classes—first, those which depend upon gravity or magnetism, and, second, those which depend upon centrifugal force or other pressure mistaken for moving power; 2. the mode of motion of such a machine; 3. by a popular abuse of the term, a movement or machine which could go on indefinitely by its own self-generated power. Thus, if a man should pretend to have a wheel which turned upon its bearings without resistance, so that it would go on moving indefinitely, or to have a fluid which, though viscous, was frictionless, so that its motion, though continually decreasing, never came to rest, neither claim would be a claim to a perpetual motion, nor (however unfounded) would it violate any fundamental principle of mechanics. On the other hand, a machine (such as has actually been proposed) which would not go on moving of itself forever, but would require a little external force to overcome friction, but which with that little force should be capable of doing an indefinite amount of work, would, properly speaking, be a perpetual motion. [perpetual, adjective, from Middle English perpetuel, from Old French perpetuel, French perpétuel = Old Spanish perpetual = Italian perpetuale, from Medieval Latin perpetualis, ‘permanent’, Latin perpetualis, ‘universal’, from perpetuus, ‘continuing throughout’, ‘constant’, ‘universal’, ‘general’, ‘continuous’ (hence Italian, Spanish, Portuguese perpetuo, Old French perpetu, ‘perpetual’), from per, ‘through’ + petere, ‘fall upon’, ‘go to’, ‘seek’; see petition; motion, noun, from Middle English motion, mocion, from Old French motion, from French motion = Spanish mocion = Portuguese moção = Italian mozione, from Latin mōtio(n)-, ‘a moving’, ‘an emotion’, from movere, pp. motus, ‘move’; see move]. ~ (Century Dictionary and Cyclopaedia).

• perpetual motion (n.): the expression perpetual motion, or perpetuum mobile, arose historically in connection with the quest for a mechanism which, once set in motion, would continue to do useful work without an external source of energy or which would produce more energy than it absorbed in a cycle of operation. This type of motion, now called perpetual motion of the first kind, involves only one of the three distinct concepts presently associated with the idea of perpetual motion.

1. Perpetual motion of the first kind refers to a mechanism whose efficiency exceeds a hundred percent. Clearly such a mechanism violates the now firmly established principle of conservation of energy, in particular that statement of the principle of conservation of energy embodied in the first law of thermodynamics (indeed, the first law of thermodynamics is sometimes stated as “A perpetuum mobile of the first kind cannot exist”).

2. Perpetual motion of the second kind refers to a device which extracts heat from a source and then converts this heat completely into other forms of energy, a process which satisfies the principle of conservation of energy. A dramatic scheme of this type would be an ocean liner, which extracts heat from the nearly limitless oceanic source and then uses this heat for propulsion. This type of perpetual motion is, however, precluded by the second law of thermodynamics which is sometimes stated as “A perpetuum mobile of the second kind cannot exist”.

3. The third type of perpetual motion is, in contrast to the two types described above wherein useful output was the goal, merely a device which can continue moving forever. It could result in actual systems if all mechanisms by which energy is dissipated could be eliminated. Since experience indicates that dissipative effects in mechanical systems can be reduced, by lubrication in the case of friction, for example, but not eliminated, mechanical perpetual motion of the third kind can be approximated but never achieved. An example of a genuine case of this kind occurs in a superconductor. If a direct current is caused to flow in a superconducting ring, this current will continue to flow undiminished in time without application of any external force. ~ (McGraw-Hill Concise Encyclopaedia of Physics).

• Perpetual motion is motion of bodies which continues indefinitely. A perpetual motion machine is a hypothetical machine which can do work indefinitely without an energy source. This kind of machine is impossible, as it would violate the first or second law of thermodynamics. (...). The history of perpetual motion machines dates back to the Middle Ages. For millennia, it was not clear whether perpetual motion devices were possible or not, but the development of modern theories of thermodynamics has shown that they are impossible. Despite this, many attempts have been made to construct such machines, continuing into modern times. (...). There is a scientific consensus that perpetual motion in an isolated system violates either the first law of thermodynamics, the second law of thermodynamics, or both. (...). The term “epistemic impossibility” describes things which absolutely cannot occur within our current formulation of the physical laws. This interpretation of the word “impossible” is what is intended in discussions of the impossibility of perpetual motion in a closed system. The conservation laws are particularly robust from a mathematical perspective. For example, if the true laws of physics remain invariant over time then the conservation of energy follows. On the other hand, if the conservation laws are invalid, then the foundations of physics would need to change.

Scientific investigations as to whether the laws of physics are invariant over time use telescopes to examine the universe in the distant past to discover, to the limits of our measurements, whether ancient stars were identical to stars today. Combining different measurements such as spectroscopy, direct measurement of the speed of light in the past and similar measurements demonstrates that physics has remained substantially the same, if not identical, for all of observable time spanning billions of years.

The principles of thermodynamics are so well established, both theoretically and experimentally, that proposals for perpetual motion machines are universally met with disbelief on the part of physicists.

• “The law that entropy always increases, holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations—then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation—well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation”. (Sir Arthur Stanley Eddington, “The Nature of the Physical World”; 1927).

In the mid nineteenth-century Henry Dircks investigated the history of perpetual motion experiments, writing a vitriolic attack on those who continued to attempt what he believed to be impossible:

• “There is something lamentable, degrading, and almost insane in pursuing the visionary schemes of past ages with dogged determination, in paths of learning which have been investigated by superior minds, and with which such adventurous persons are totally unacquainted. The history of Perpetual Motion is a history of the fool-hardiness of either half-learned, or totally ignorant persons”. (p. 354, “Perpetuum Mobile: Or, A History of the Search for Self-Motive”, Henry Dircks; 1861).

persuasion (n.): any group or type of person or thing linked by a specified characteristic [‡], quality, or attribute; [e.g.]: “Pictured on the poster was a collared clergyperson *of the female persuasion*”; “There were a couple of mismatched kitchen units, a butler’s sink, an ancient gas oven *of the enamel persuasion*, a leaking radiator and an odd-legged table with a red Formica top”; “Many people *of a bohemian persuasion* passed through her living room, from artists to drug addicts, notthat those classifications were mutually exclusive”. [origin: Late Middle English: from Latin persuasio(n-), from the verb persuadere, from per-, ‘through, to completion’ + suadere, ‘advise’]. [emphases added].~ (Oxford English Dictionary).

persuasion (n.): a class that is defined by the common attribute or attributes possessed by all its members: breed, cast, description, feather, ilk, kind, lot, manner, mould, order, sort, species, stamp, stripe, type, variety.~ (American Heritage Roget’s Thesaurus).

[‡]The following examples are from a selective online sampling demonstrative of how the above definition (as in the above “any group or type of person...linked by a specified characteristic” that is) corresponds with everyday usage by the very persons thusly self-identifying. Viz.:

• “Tinky Winky’s handbag accessory makes people assume the Teletubby is *of the homosexual persuasion*...”. [emphasis added].
[www.gaynz.com/articles/publish/19/printer_4512.php].

• “Those *of the homosexual persuasion* will find themselves drawn to South Beach...”. [emphasis added].
[www.fagabond.com/cities/miami/].

• “Head to the city beaches however, and you’re likely to see a fair few hunky men *of the homosexual persuasion*...”. [emphasis added].
[https://mygaytravelguide.com/going-gay-colombia].

• “In many ways, Dorothy was the original fag hag {i.e., the ‘Dorothy Gale’ character in the 1939 “Wizard of Oz” film}. It’s no wonder that the term ‘friend of Dorothy’ has long been used as a low-key way of asking whether a guy is *of the homosexual persuasion*...”. [emphasis added].
[www.gaytimes.co.uk/culture/8905/camp-sites-wizard-oz/].

• perversive (adj.): tending or having power to pervert or corrupt. [from Latin perversus , pp. of pervertere, ‘turn about’, ‘corrupt’, ‘pervert’ (from per, ‘through’ + vertere, ‘turn’) + -ive]. ~ (Century Dictionary and Cyclopaedia).

• perversive (adj.): tending to corrupt or pervert; [e.g.]: “Collective laissez-faire gives room for perversive behaviours in the electoral process”; (synonyms): corruptive, pestiferous, contaminative; [e.g.]: “A pestiferous malignancy corrupted the entire mail-in ballot-count”; “Unaccountable money suffused their corruptive policies with meanness”; “Free handouts, contaminative throughout the electoral system, perverted its integrity”; (related terms): malevolence, wickedness; evil (vile iniquity or flagitious depravity); [e.g.]: “The whole enterprise was infused with malevolence”; “It was an all-pervasive wickedness”; “Once set in motion the evil deeds multiplied exponentially”). [1690, from Latin pervertere, ‘to overturn’, ‘subvert’, from per- (indicative of deviation) + vertere, ‘to turn’]. ~ (Online Neoteric Dictionary).

• pervicacious: very obstinate: wilful, refractory; (adv.): pervicaciously. [etymology: Latin pervicac-, pervicax, ‘pervicacious’; from per-, ‘thoroughly’ + -vicac-, vicax, from the stem of vincere, ‘to prevail’, ‘win a point’, ‘conquer’ + English -ious]. ~ (Merriam-Webster Dictionary).

• pervicacious (adj.; obs.): obstinate; wilful; refractory; (adv.): pervicaciously; (n.): pervicaciousness. [Latin pervicax + -acis]. ~ (Webster’s 1913 Dictionary).

• pervicacious (adj.; rare): extremely stubborn or headstrong; wilful, obstinate; [e.g.]: “You are recommended, Miss, to the practice of your private devotions. May they be efficacious upon the mind of one of the most pervicacious young creatures that ever was heard of!” (‘Letter XXII’, in “Clarissa. Or, The History of a Young Lady”, by Samuel Richardson, vol. I (of VII); sold at Bath, London, 1748); (adv.): pervicaciously; (n.): pervicaciousness. [etymology: from Latin pervicāx +‎ -ious]. ~ (Wiktionary English Dictionary).

• pervicacious† (adj.): very obstinate; stubborn; wilfully contrary or refractory; wilful; [e.g.]: “Why should you be so pervicacious now, Pug? Pray take three hundred”. (John Dryden, “Mr. Limberham; or, the Kind Keeper”, ii. 1). [= Portuguese pervicaz = Italian pervicace, from Latin pervicax (pervicac-), ‘firm’, ‘determined’, ‘obstinate’, from pervincere, ‘maintain one’s opinion’, from per, ‘through’ + vincere (√vic), ‘conquer’: see victor]. ~ (Century Dictionary and Cyclopaedia).

• pervicacious (adj.): 1. stubbornly, and usually unreasonably, holding to an opinion, decision or purpose; (synonyms): intransigent; adamant; pertinacious; pigheaded; hardheaded; bullheaded; adamantine; uncompromising; ossified; renitent; thrawn; stiff-necked; hard-nosed; bloody-minded; as stubborn as a mule; determined to have one’s own way; with a will of one’s own; 2. refusing to obey authority; (synonyms): recalcitrant; contumacious; obstreperous; obdurate, wilful, headstrong, refractory; recusant; intractable; contrarious; fractious. ~ (Word-Hippo Thesaurus).

• “Of late, I am told by shopkeepers, the tin box with the pervicacious cover is becoming popular; but I remain true to my sponge in a bottle: for, unlike the leopard, I am able to change my spots”. ~ (“The Perfect Gentleman”, Ralph Bergengren 1909).

• “If ‘sortilegious’ is admitted, ‘sortilege’ should be so as well; if ‘pervicacious’, then ‘pervicacy’ ⁽⁰¹⁾, which it assumes, and which has been in actual use, should not be left out, as it is by Charles Richardson, and, which is the same thing, left without an example by Henry Todd”.

⁽⁰¹⁾[Footnote]: “The Independents at last, when they had refused with sufficient pervicacy to associate with the Presbyterians, did resolve to show their proper strength”. (page 104, “Life of Richard Baxter”, 1696, by Matthew Sylvester, 1636-1708). ~ (page 23⁽⁰²⁾, “On Some Deficiencies in Our English Dictionaries”, Richard Chenevix Trench, DD, Dean of Westminster; published 1860, by John W. Parker & Son, London).

⁽⁰²⁾ [https://archive.org/details/transactions00philuoft/page/n179/mode/1up]

pi (n.): 1. the sixteenth letter in the Greek alphabet (Π, π), a consonant, transliterated as ‘p’; 2. a transcendental number, fundamental to mathematics, which is the ratio of the circumference of a circle to its diameter; approximate value: 3.141592+; symbol: π. [C18 mathematical use from Greek π, representing the first letter of Greek περιφέρεια (periféreia), ‘periphery’, ‘circumference’]. ~ (Collins English Dictionary).

piss-weak (slang, vulgar): extremely weak’. ~ (Wiktionary English Dictionary).

• pleonastic (adj.): repetition of same sense in different words; [e.g.]: “‘a true fact’ and ‘a free gift’ are pleonastic expressions”; (synonyms): tautologic, tautological, redundant; [e.g.]: “the phrase ‘a beginner who has just started’ is tautological”; “at the risk of being redundant I return to my original proposition”. (J. B. Conant); prolix (tediously prolonged or tending to speak or write at great length); [e.g.]: “editing a prolix manuscript”; “a prolix lecturer telling students more than they want to know”. ~ (Princeton’s WordNet 3.0).

• pleonastic (adj.): using or containing an excessive number of words; (synonyms): diffuse, long-winded, periphrastic, prolix, redundant, verbose, wordy. ~ (The American Heritage Roget’s Thesaurus).

• pleonasm (n.): 1. the use of more words than necessary or an instance of this, such as a tiny little child; 2. a word or phrase which is superfluous; (adj.): pleonastic, pleonastical; (adv.): pleonastically. [C16: from Latin pleonasmus, from Greek pleonasmos, ‘excess’, from pleonazein, ‘to be redundant’]. ~ (Collins English Dictionary).

• pleonasm (n.): 1. the use of more words than are necessary to express an idea; redundancy; 2. an instance of this, as in ‘a free gift’; (adj.): pleonastic; (adv.): pleonastically. [1580-90; from Late Latin pleonasmus, from Greek pleonasmós, ‘redundancy’, ‘surplus’, derivative of pleonázein, ‘to be more than enough’, derivative of pleíōn, ‘more’]. ~ (Webster’s College Dictionary).

• pleonasm (n.): 1. (a.) the use of more words than are required to express an idea; redundancy; (b.) an instance of pleonasm; 2. a superfluous word or phrase; (adj.): pleonastic; (adv.): pleonastically. [Late Latin pleonasmus, from Greek pleonasmos, from pleonazein, ‘to be excessive’, from pleōn, ‘more’]. ~ (American Heritage Dictionary).

• pleonasm (rhetoric): 1. the use of more words than necessary or an instance of this, such as ‘a tiny little child’; 2. a word or phrase which is superfluous. ~ (Collins Discovery Encyclopaedia).

• pleonasm (n.): 1. the use of unnecessary words to express an idea; redundancy; 2. an instance of this, as true fact; 3. a redundant word or expression; (adj.): pleonastic. ~ (Ologies & Isms Dictionary).

• pleonasm (n.): a superfluous word or phrase, or the use of more words than necessary. ~ (Dictionary of Unfamiliar Words by Diagram Group).

• pleonasm (n.): using more words than necessary; [e.g.]: “a tiny little child”; (synonyms): verboseness, verbosity (an expressive style which uses excessive or empty words). ~ (Princeton’s WordNet 3.0).

polemicist (n.): a writer who argues in opposition to others (especially in theology); (synonyms): polemic, polemist. ~ (Princeton’s WordNet 3.0).

• posit (tr.v.): 1. to lay down or assume as a fact or principle; postulate [viz.; to claim or assume the existence or truth of, esp. as a basis for reasoning or arguing]; 2. to place, put, or set; (n.): 3. something posited; assumption; postulate [viz.: something taken as self-evident or assumed without proof as a basis for reasoning]. [1640-50; from Latin positus, past participle of pōnere, ‘to place, put’].~ (Webster’s College Dictionary).

• posit (v.): to take for granted without proof; (synonyms): assume, postulate, premise, presume, presuppose, suppose; informal: reckon.~ (American Heritage Roget’s Thesaurus).

position (chiefly Logic & Philos.): the action of positing; the putting forward of a proposition; affirmation, postulation (now rare); a proposition laid down or stated; something posited; an assertion, a tenet. (Oxford Dictionary).

postpuberal (post-pubertal): occurring in or pertaining to the period following puberty; postpubescent⁽*⁾. ~ (Miller-Keane Encyclopaedia and Dictionary of Medicine, Nursing, and Allied Health).

• pother (n.): an excited state of agitation; [e.g.]: “there was a terrible pother about the theft”; (synonyms): dither, fuss, tizzy, flap; agitation (a mental state of extreme emotional disturbance); (v.): 1. make upset or troubled; (synonyms): charge up, commove⁽*⁾, agitate, rouse, excite, turn on, charge (cause to be agitated, excited, or roused); 2. make a fuss; be agitated; dither, flap; fret, fuss, niggle (worry unnecessarily or excessively). ~ (Princeton’s WordNet 3.0).

⁽*⁾commove (v.): 1. cause to be agitated, excited, or roused; 2. change the arrangement or position of. ~ (Princeton’s WordNet 3.0).

• pother (n.): a tumult; disturbance; confusion; bustle; flutter; [e.g.]: “We run, we strive, and purchase things with our Blood and Money, quite foreign to our real intrinsic Happiness, which have a Being in Imagination only, as you may see by the Pother that is made about Precedence, Titles, Court-Favour, Maidenheads and Chinaware”. (Sir Richard Steele, “The Funeral: Or, Grief A-la-mode”, 1701, I. 1.). ~ (Century Dictionary and Cyclopaedia).