The monthly programs are an essential element of CDHS. Our programs support our humanist goals of exchanging ideas, heightening our knowledge of the world and ourselves, fostering moral and ethical growth, and promoting the principles of secular humanism. This archive of summaries of past programs provides an overview of the varied subjects addressed.
Passing the Global Espionage Torch: How Britain Helped the US Expand its Eavesdropping Capabilities
Kristie Macrakis teaches at Georgia Tech in Atlanta. Her talk was titled "Passing the Global Espionage Torch — How Britain Helped the U.S. Expand its Eavesdropping Capabilities." This was excerpted from her forthcoming book, Techno-Spy Empire, about using technology in espionage.
The subject really concerns the gathering of intelligence, e.g., concerning terrorism or other kinds of national security threats. It's basically divided into two genera: "Signals Intelligence" or SIGINT, derived from electronic communications, and "Human Intelligence," or HUMINT, gathered by spies.
Before WWII the British, with their global empire and corresponding global concerns, were the premier practitioners. As Macrakis' title indicated, her talk focused mainly on the Brits passing that torch to America, while still remaining very much in the game, as our partner. She traced the partnership to the WWII era with a close relationship between William Friedman, a U.S. cryptographer, and Edward Travis, Britain's SIGINT head, who worked on the famous breaking of the Nazi cryptography "enigma machine" at Bletchley Park.
The cooperation evolved, in 1954, into the "Five Eyes" — bringing in as well Canada, Australia, and New Zealand. They, together with the U.S. and U.K., are the core group, assisted by others as part of a larger "Fourteen Eyes" intelligence-sharing club. Macrakis also made reference to "Echelon," the monicker for a global eavesdropping network revealed by Edward Snowden.
After the war, as Britain decolonized, Macrakis said, they traded territory for U.S. technology and money. Involving a string of island bases for intelligence gathering, notably on Cyprus, and Diego Garcia, an island in the Indian Ocean, which actually became a new colony in 1965. America provided much of the financing to sustain these bases. There's a giant data center in Utah just for storing all the information collected. Macrakis described the whole system as a "secret empire," operating below the awareness of most of the rest of the world.
Good Vibrations: The Interplay of Music and Physics
Laurie McNeil is a professor of Physics at the University of North Carolina. Her talk was titled, "Good Vibrations — the Interplay of Music and Physics." Actually an explanation of how music works in terms of the physics.
She started with the question, what is musical sound? For the musician, it's about things like notes and pitch. For the physicist, sound waves and frequency. Whereas musicians speak of timbre, physicists would put it in terms of frequency spectrum. A musical sound consists of multiple frequencies, the amounts of each creating what we call timbre. Different instruments playing the same notes are differentiated by their timbre.
McNeil discussed in turn various categories of musical instruments, delving into the physical aspects of how they produce sounds. Stringed instruments do so by modulating speed as determined by the tension and mass density in the strings, producing different sound wave patterns. A shorter string produces a higher note; also achievable by tightening the string (increasing tension) or using a thinner string (decreasing mass density).
She noted that as a wave propagates across a string, portions of it move up and down while others (nodes) are stationary. The frequencies are in whole number ratios; required for the ear and brain to perceive a distinct pitch. Each standing wave has its own frequency, the ratios between them corresponding to musical intervals, or octaves. For example, a 3:2 ratio is a perfect fifth; a 4:30 a perfect fourth.
For wind instruments, it's a matter of pressure waves in an air column. Note that a flute is open at both ends, a clarinet closed at one end, thus creating different resonances in their air columns. The shape of the tube matters too. A brass instrument has one closed end and a conical bore. Its valves are used to change the tube length.
In the case of percussion, it's vibrations of rods and membranes. McNeil pointed out that an ordinary drum doesn't produce pitch, but a kettle drum does, because the air in the basin changes the resonant frequencies to make them closer to whole number ratios.
Understanding all of this is, of course, not necessary for the enjoyment of music.
The Q&A included some discussion of how differences among instruments in the same class can produce different sound quality, the classic case in point being the Stradivarius violin. But Fred Levine observed that the quality of the player can matter more than the quality of the instrument, and a skilled player can make even a lousy instrument sound good.
And, in concluding her talk, McNeil quoted Duke Ellington that "if it sounds good, it IS good."
BLASPHEMY: A Medieval Concept with Modern Consequences
John M. Suarez, M.D. is a retired UCLA Professor of Psychiatry. His topic was "Blasphemy: A Medieval Concept with Modern Consequences."
He began by displaying our First Amendment, guaranteeing the free exercise of religion — which includes freedom to reject religion. Indeed, to blaspheme. Blasphemy is defined as insulting, contempt for, or lack of reverence for God. But the concept has been expanded to socio-political contexts, being applied against artistic, political, scientific, and literary expression. In other words, any non-conforming expressions.
While earlier Western societies punished blasphemy, the issue became largely moot with the Renaissance and Enlightenment. Though some American states actually still have anti-blasphemy laws on the books. The Supreme Court has never had occasion to rule on this.
Meantime, most Muslim nations outlaw blasphemy, with punishments including death, and the comfy chair. The issue came to the fore with the 1989 Fatwa by Ayatollah Khomeini against Salman Rushdie for authoring The Satanic Verses, seen as blasphemous. Rushdie had to go into hiding; a Japanese translator was killed. Later a Dutchman Theo Van Gogh, was murdered for making a film considered blasphemous. And of course there was the "Danish Cartoon" affair, satirizing Mohammad, and the Charlie Hebdo magazine attack.
Nine-eleven also brought the issue to the fore, spotlighting terrorism in the name of Islam. The Muslim world reacted with sympathy but was wishy-washy about actually condemning the attacks; which provoked a Western backlash against Islam; and then Muslim demands for punishments for "insulting Islam."
Suarez said that while basically the West focuses on the rights of individuals, the Muslim World privileges instead the protection of religion. Suarez noted that the UN has performed a balancing act between vaunting human rights and accommodating blasphemy laws; it has stopped short of condemning "defamations of religion" as demanded by some Muslims. But many European nations have acceded to such demands, banning "hate speech" critical of religion. The U.S., in contrast, remains committed to the free speech guaranteed by the First Amendment.
Suarez said that punishing blasphemy stifles independent thinking and thus perpetuates conformity and preservation of the status quo. This keeps the Muslim world from reconciling with modernity; what it needs is a Reformation and Enlightenment.
He noted that many in the Muslim world accused of blasphemy are subjected to violence. There is a program, Secular Rescue, part of the Center for Inquiry, aimed at aiding and protecting such voices, including relocating them to safety.
Adam Seyhan is a retired engineer whose presentation concerned the so-called climate change hoax.
He started by posing the question, are we having more storms, heat waves, floods, and suchlike disasters? The answer is yes. In 2019 we saw vast fires in Australia, Siberia, the Amazon (80,000 fires there) and of course California. This included the three largest fires ever. Floods plagued the U.S. (affecting 14 million people), Iran, Australia, Pakistan, the U.K., and Venice. Japan had flooding and a heat wave; one in India saw temperatures exceeding 120 degrees. Cyclone Idai in Southeast Africa was deemed the deadliest ever in the Southern Hemisphere.
That was 2019. Good thing 2020 was problem-free.
Seyhan also charted the annual incidence of U.S. storms costing over $1 billion in damage, rising from 2.9 to 22 over four decades.
While typically no individual event can be attributed to global warming, temperatures are clearly rising
(Seyhan said by nearly a degree in the last forty years) and that affects how the planet behaves. Dry regions get dryer and the wet get wetter. Warmer air causes more evaporation from the oceans, creating more rain. But sea levels are not sinking; to the contrary, melting ice raises them. Arctic ice has fallen by a third. Seyhan focused on the Thwaites Glacier in Antarctica, one of a bunch, but called the "Doomsday Glacier" because that one alone could raise sea levels by 7-10 feet. Antarctica has 90% of the planet's ice; melt all of it and the rise could be 200 feet. A lot of people would need to find alternate accommodations. Is the climate change we're seeing cyclical? Unfortunately not. Solar activity is on an 11-year cycle, but right now we're at a minimum, the peak expected in mid-2025.
Global warming is caused mainly by the greenhouse effect: certain gases in the atmosphere blocking the escape of the heat from solar radiation. The main concern is Carbon Dioxide, but methane's warming effect is actually at least 28 times greater over 100 years. Cows emit a lot of methane; that could be significantly reduced by tweaking their diets.
Seyhan noted that 57% of greenhouse gases are emitted by just four countries: China, America, Russia, and India. [Well, pretty big countries.] America's contribution is 15%, but our emissions peaked in 2007 and have been dropping since. However, Seyhan noted they still equate to 1.5 million truckloads of coal daily. Eating a pound of chicken entails 4.57 pounds of Carbon Dioxide; one hour on a flight 200 pounds.
He said we need to get down to zero emissions by 2050 to avoid climate disaster. Is there any hope? Seyhan pointed to a recent International Energy Agency report, and a book by Bill Gates, showing how it can be done. A global climate conference is scheduled for September in Scotland (weather allowing).
Seyhan presented a long list of proposals. Topping it is a worldwide carbon tax; along with punishments for nations not on board. He said we must ban use of fossil fuels, and then even natural gas. Nuclear power would be part of the replacement. Also hydrogen as fuel.
What can an individual do? Reduce waste, Seyhan said; use electric cars and heat pumps, LED lighting, solar panels; eat less meat; pressure politicians.
Unspoken was the fact that if God wanted lower temperatures, he'd reduce them.
The dangerous rise of the religious right
Katherine Stewart is an investigative reporter and author of the book, The Power Worshippers. Her talk was titled "The dangerous rise of the religious right."
She began by saying "Christian nationalism" would be a better descriptor. Central to the ideology is the (historically false) idea of America founded as a Christian nation. But this is actually more about politics than religion. And it's a vast powerful force, a defining feature of our political landscape; threatening our democracy. January 6 showed that.
Stewart divided her talk into five basic topics.
First, this did not originate as some spontaneous movement from the heartland, a reaction to the social changes starting in the '60s. Instead it was organized from the top down, by people whose real agenda is gaining power for themselves and their ilk. They constructed a huge national advocacy and messaging infrastructure, seeking government support for their movement, through measures that privilege it over other societal actors.
Stewart later quoted Supreme Court Justice Scalia (an outspoken Christian), ruling against a religious exemption for peyote use, saying we can't let everyone decide what laws to obey based on their religious beliefs. Yet, said Stewart, that is actually exactly what the religious right is seeking.
Her second point was that the movement is, again, politically driven. The "culture war" stuff is really secondary; indeed, weaponized tools to serve the political agenda. In particular, the abortion issue did not create the religious right; rather, the issue was created to serve the political aims. When Roe v. Wade was decided, most Christians actually supported abortion law liberalization. But new right leaders nevertheless latched onto abortion as an issue that could be exploited to manipulate a sizable voter base and ignite a hyper-conservative counterrevolution. Stewart argued that these leaders do not actually want to minimize abortions; what they really want is to keep the issue boiling.
Third, she saw a tie-in with the rise of extreme income inequality, which gives rise to conspiratorial thinking and other kinds of irrationalism, endemic on today's American right.
Fourth, this movement has always been anti-democratic and authoritarian. Not just another set of voices contending in the public square. Its leaders don't really imagine they can prevail by persuading a voting majority to their point of view. Instead they aim to prevail by flouting it, having contempt for democratic processes and the idea of the common good. This again was exemplified on January 6. Stewart noted that other authoritarian leaders, like Putin and Erdogan, have similarly exploited religion as a vehicle for political power without democracy.
Fifthly, she saw the movement as inseparable from racism, though the connection is complex. The voter suppression that is part of its tool-kit for holding power undemocratically targets ethnic minorities. There are notions of "purity" versus impurity, and an emphasis on concepts of identity and appeals to a heritage culture (read: white).
Stewart said that the religious right is far more organized and focused than its opponents. We need a range of voting reforms to stymie undemocratic techniques like gerrymandering and voter suppression. But while the movement fully understands the importance of voting, others are more casual about it. Failing to realize how much is really at stake.
At the end of the day, Stewart opined, the narrow-minded Christian nationalist vision embodies what would be a weak society, not a strong one.
Life After Deaf: My Misadventures in Hearing Loss and Recovery
Noel Holston spoke about his experiences related in his book, Life After Deaf - My Misadventures in Hearing Loss and Recovery.
Born in Mississippi, he had a career in journalism, starting out as a reporter, and becoming a TV critic for the Orlando Sentinel and Newsday. He described himself as "unscathed" until waking up one morning in 2010 with hearing gone. The cause remains unclear; it seems to have been an autoimmune thing.
Various attempts to treat the problem with drugs did not work. Finally, recourse was had to a cochlear implant. Holston explained that this is not akin to a hearing aid. Instead, it's a mini-computer that translates sounds into digital impulses, sent down a wire into the relevant area of the brain, which then in turn translates the data into what it makes sense of in a way similar to how it interprets sounds received in the normal fashion. The implant is installed in the skull by boring a hole. Holston likened it to a root canal.
After the surgery, at first the sounds seem like gibberish; it takes some time and effort for the brain to learn the new system, and eventually to understand spoken words. Holston said it was a two year struggle for him, and even then, not very successful. Finally the problem was discovered: a wire had worked its way out and was dangling in his ear canal. This necessitated pulling out the cochlear implant and re- installing a new one, a do-over, with the whole learning process restarted. This time the results were better.
Holston is now able to function quite well hearing and speaking words. However, he said he'd always been "marinated" in music; he married a singer; but his ability to enjoy music is still much impaired, because the implant system does not allow for the range and nuances of sound that music entails. Holston said he's now able to appreciate music that he's very familiar with, so his memory fills a lot in. But new music can't do much for him.
He characterized his book as really being about learning to live with limits and challenges. Getting "scathed" makes one grow. "What doesn't kill me," he said, "makes a good story."
Quackery: A Neglected Population Health and Societal Menace
Dr. Bill London is a professor of public health at Cal State LA, and editor of Consumer Health Digest. His topic was "Quackery: a neglected public health and societal menace."
The key concept in defining the quackery he talked about is promotion — of health products, services, or practices of questionable effectiveness or validity for intended purposes. Unproven effectiveness itself does not necessarily denote quackery. Medical practitioners can responsibly try unproven therapies in certain circumstances, where better alternatives are not available. Responsible practitioners are not promoters. But Dr. London also said that true believers can be more dangerous than intentional deceivers.
He presented a hierarchy of scientific evidentiary support for medical treatments. Topped by randomized controlled trials. But he noted that it matters how well such studies are done. And lower down are "pre-clinical" studies that can provide a basis for further testing. London cautioned about the importance of having a plausible hypothesis to support such testing; if you test for something whose underlying theory is implausible, there's a danger of false positives.
London listed varieties of "quackogenic harm." There's direct harm when the treatment is actually bad for the user. Indirect harm, more common, where it interferes with the person getting proper medical care. There's financial harm — wasting money. Psychological harm of various kinds. And societal harm, eroding our foundation of shared truth.
An audience participation effort identified red flags for quackery and why people fall for it: among them, distrust of the medical/pharmaceutical establishment; fears; confusion about the natural causes and courses of illnesses; and seductive tropes like "natural," "helping the body heal itself," "purity," "mind-body," et cetera. Religion, spiritualism, mysticism, and ideologies come into play.
London cited a 1984 Congressional Committee report calling quackery a $10 billion scandal. And some other documents of similar vintage — saying that this actually shows this has been a neglected problem. Indeed, he noted that the government itself has muddied the waters, having in 1992 (responding to political pressure from Iowa Senator Tom Harkin) created an "Office of Alternative Medicine" at the National Institutes for Health; later renamed the "National Center for Complementary and Integrative Health."
London sees this as giving undue legitimacy to what is really still quackery. With "alternative medicine" a euphemism that has achieved some cachet in the public eye. He quoted Richard Dawkins that something can't be false in the ordinary sense but true in an "alternative" sense (as with "alternative facts.") London said there's only medicine.
Now there's been a move to replace the term "alternative medicine" with "complementary medicine," with the idea of mainstream practitioners using it together with "conventional" medicine. Which London thinks should better be termed "regular medicine." And he particularly hates the "integrative" word here, crafted for positive associations. We don't, he said, "integrate" fantasy with reality.
London got some pushback from attendees who accused him of a black-and-white take, and said they'd benefited from what they took to be non-conventional medicine. In response he acknowledged that regular medicine has a lot of deficiencies, especially in treating "the whole person" which, though it might sound touchy-feely [my term: FSR] is actually important. In this regard he spoke about the placebo effect, a major factor in medicine.
This was particularly relevant when he addressed questions about acupuncture and chiropractic, both raising complex questions, and which have elements that make patients feel better even if what they do may actually be medically nugatory. Regarding acupuncture, he said that in controlled studies, the tighter the controls, the smaller the actual physical impact shown. Suggesting that acupuncture is a "theatrical placebo."
Charged Humor from McCarthyism to Covid
Beck Krefting is Chair of American Studies at Skidmore. Also a former standup comic. Her academic work concerns social and cultural issues around humor. Krefting's CDHS talk was titled, "Charged Humor from McCarthyism to Covid." She said her aim was not to make us laugh; and indeed, the presentation was fairly laugh-free.
She began by explaining what she means by "charged humor." As distinguished from ordinary humor. Charged humor has an edge based on projecting some viewpoint about social or cultural matters. It can both attract and repel hearers. She said that it spotlights problems and also points toward solutions. Krefting also said its being charged is not incidental or accidental; it's clear what the comic is up to, and they cannot be misunderstood.
She sought to present an "historical through-line." The story begins with blackface minstrelsy, which Krefting deemed the earliest standup comedy. Emerging in the 1700s, the performers were originally Black, and they were actually mocking white European pretensions; only in 1840s did minstrelsy change to denigrating Blacks, becoming much more popular.
Around the turn of the 20th century, Vaudeville was the primary venue for comedy performance. There were some Black Vaudevillians — who, Krefting said, were forced to caricature themselves. Standup in its modern form emerged around mid-century, with a big boom occurring in the 1980s with a proliferation of comedy clubs. This also entailed the rise of "shock comedy," not doable on network TV, but gaining a wide audience through clubs and also cable TV.
Krefting noted that while there were niche audiences for such material, a comic could not make a big mainstream career from it. But she cited the case of George Lopez, who did make a big name for himself with "family-friendly" comedy on network TV but then went on, building from that, to edgier "charged" humor.
Meantime, however, the routes for bucking conventional standards were growing. Krefting spoke of comics doing not simple jokes with punchlines but rather telling stories. And, in particular, new opportunities for them to flourish in genres outside the traditional ones. Women, especially, who'd been unwelcome in old-line comedy could now spread their wings. Krefting went on to talk about further niches — African-American comedy (which, while the larger comedy boom fizzled in the 1990s, became much more prominent); Arab-American comedy in the wake of 9/11; and queer comedy.
Audiences, she said, were hungry for such fare. And they got hungrier after the 2016 election, which kind of demanded attention being paid. Then there was the rise of the metoo and BLM movements, with a similar effect. All this made comics feel they had to start being more meaningful, in a time of historical reckoning; and Krefting saw them as rising to the challenge.
But, meantime, she also spoke of pushback. For example, the metoo movement widely being seen as going too far, women being cast as a bunch of whiny complainers. And there is also a genre of alt-right charged humor.
All of which goes to show that comedy is, indeed, no laughing matter.
Police/Community Reform in a Time of Turmoil and Social Change
Terry O'Neill is an attorney specializing in police-related matters. He spoke about his experiences in the context of currently prominent issues and a longtime overall problem of systemic racism.
Relations between policing and, particularly, minority communities have indeed been fraught; brought to the fore by the recent George Floyd and Breonna Taylor killings and others. O'Neill also discussed the death of Daniel Prude in Rochester. These cases gave new energy to the "Black Lives Matter" movement and efforts to "Defund the Police" (a politically maladroit slogan which O'Neill explained really means shifting funding from police to other kinds of interventions).
He pointed to COMPSTAT, a program originating with New York City's police in the 1990s, aiming for data-guided policing. The idea being to devote police resources to areas statistically shown to need them most. But Black communities felt this meant singling them out for unwelcome police aggressiveness. O'Neill said this was aggravated by "stop-and-frisk" policies that caused a lot of ugly interactions between police and minority citizens, with actually very few resulting arrests or finding drugs or guns. And when "stop-and-frisk" was ended, crime did not rise, but continued falling.
O'Neill said the biggest problem for police forces is to build trust and respect in the communities they serve. This has been the focus of "community policing" efforts. However, there is a tendency among police forces to feel that the way they've always done things is the right way, so they are resistant to change. Reform often being forced upon them by outside forces, such as the courts. Meantime, communities often feel they don't get the policing they need, while what they do get disserves them, causing tension and alienation.
Accountability is a key issue. O'Neill said people demanding reform often don't really know what they should be asking for. He noted that since 2000, Albany has had a citizens' review panel — but it has never consummated disciplinary action against a police officer. The panel simply lacks teeth. Right now efforts are underway in Albany to do something about this.
But pushing back against accountability are powerful police unions. They wield political clout because elected officials are afraid of them, lest they be branded "soft on crime." Such unions have been very successful at negotiating contracts that make it almost impossible to discipline officers for misconduct.
Looking toward a way forward, O'Neill also discussed his experience relating to Northern Ireland, with a long history of severe police abuses. There, an ombudsman was introduced to facilitate oversight; and also a policy of hirings to better reflect community makeup (in that case, hiring as many Catholics as Protestants.)
Why You Can't Trust Your Brain
Dr. Caleb Lack, at the University of Central Oklahoma, is a clinical psychologist and author of six books. His topic: Why You Can't Trust Your Brain.
Well, whose brain can you trust? Actually, the brain is an extremely complex organ, with 86 billion neurons (give or take maybe a dozen), and 100 trillion connections. But it's easily fooled — by itself.
Dr. Lack said "doubting yourself" has negative connotations, but it's actually the hallmark of an enlightened mind. Being a critical thinker and skeptic is hard to actually do. The problem is the human brain being "logically illogical." That is, there are reasons why it does what it does, programmed by evolution.
Two key factors are cognitive biases — predictable patterns of judgment — and mental heuristics — shortcuts or general rules of thumb to decrease effort in decision-making. These tend to oversimplify reality and cause systematic decisional errors. But they are not all bad. We don't always make bad decisions. In fact, there's a "less is more" effect — folding too many factors into a decision may impede a positive outcome. And we can never have access to all the information, and must act on what we do have. That means "good enough" decision making. As opposed to investing too much effort in a decision. That's why we did develop these seeming cognitive quirks — they are actually adaptive in balancing between effort and result.
Dr. Lack focused on two related metal biases: confirmation bias and belief perseverance. The former is the tendency to welcome information confirming already held beliefs or ideas. We discount any problems undermining that information, and recall it later. The other side of the coin is that information at odds with one's belief is discounted, nitpicked, and soon forgotten. The more emotionally charged a belief is, the more deeply held, the more confirmation bias applies. This is why we developed the scientific method, whose raison d'être is subjecting theses to attempts to disprove them.
Belief perseverance is (surprise) the tendency to stick with an initial belief even after seeing disconfirming information. Indeed, that actually causes people to "dig in." That's why it's generally pointless to argue with persons adhering to a certain political party or personage, which will go nameless here. Not to mention religious believers.
Dr. Lack spoke about three manifestations of belief perseverance. One concerns self-impressions, beliefs we hold about ourselves. Another he called "social impressions," beliefs about other groups of people — like, oh, I don't know, maybe certain ethnicities. The third is "naive theories" about how the world works. As an example he gave the Sun appearing to move around the Earth. Though many of us have gotten wise to this.
He also spoke about illusory correlations — seeing relationships between things not actually connected. The word pareidolia applies to interpreting random stimuli as being something particular. An example was the "face on Mars," a geographical feature which, photographed in certain light, looked like a human face. We are in fact especially apt to see faces everywhere, a biological adaptation, because interacting with other people is so important for our thriving. More generally, we are subject to patternicity, seeing all sorts of patterns where they don't exist. Also adaptive: you're better off wrongly seeing a bunch of pixels as a predator than making the reverse mistake. And agenticity is when you see patterns as being caused by something. Like a deity. These cognitive quirks are big reasons why we have religion.
Another example Lack discussed was a spate of concern in the '70s and '80s that Rock music had "backmasking" — Satanic messages when played backwards. Lack played an example. He deemed it pretty far fetched to imagine musicians actually managing this trick — or anyone being influenced by messages almost impossible to decipher.
A final phenomenon he spoke about was priming — the influence of "implicit nonconscious memory" — stimuli in one context affecting behavior in another. He displayed a woman's face. Then an image which could be seen as either a saxophone player or a woman's face. Having been primed by the first image to see a woman's face, that's what we saw in the second.
Dr. Lack concluded by saying we can't rid ourselves of cognitive biases but can decrease their effects. One must examine one's own beliefs, and use tools like the scientific method. And humility, he said, is crucial to critical thinking.