Culture describes the social norms of a society described by beliefs, customs, laws, and habits acquired over time.  The Cambridge English Dictionary identifies culture as "the way of life, especially the general customs and beliefs, of a particular group of people at a particular time”.    Culture serves as a guide for behavior, dress, language, and demeanor in a situation, which serves as a template for expectations in a social group.  For example, in a military culture, valor is a typical expectation for an individual while duty, honor, and loyalty to the unit are virtues for members of the unit.  Similarly, in a religious culture, adoption and profession of of common beliefs is expected while group members support each other and the core principles of their culture.

Evolution of culture coincides with the evolution of the laws of nature, development of the understanding that the universe seems to have an internal order that can be described.  This understanding lead to the ultimate dissolution of the belief that everything that happened in life was controlled by the gods.

In the 6th century BC, Anaximander (610-546 BCE) hypothesized that man could not have been created as an infant because infants are helpless at birth.  This stimulated the first thoughts about evolution - man must have evolved from other similar species, it could not have happened any other way.  Much later in evolution, people were stoned to death by various religions for articulating such irrational thoughts. 

The first  mathematical formulation of the law of nature was developed by Pythagoras (580-490 BCE) who developed the theorem that described the the square of the hypotenuse (the longest side of a right triangle) is equal to the sum of the squares of the of the other two sides.  Evidence of this application is on the Greek Island and Samos, a tunnel bored through a mountain to allow the Greek army to approach the back side of the Turkish army on the other side of the mountain.  Pythagorus also developed the understanding of the relationship between the length of a string and its harmonic vibration frequency applied to various string instruments.

In the 5th century BC, Democritus (460-370 BCE) concluded that all things in the universe were comprised of small particles, calling them fundamental particles.  Democritus named the fundamental particles "atoms" based on the Greek term for "uncuttable"; one could not cut anything smaller than an atom.  2,100 years later, this concept would be rediscovered by chemists and physicists.

Socrates, a Greek living in the 4th century BCE is credited with accumulating knowledge of and articulating the early beliefs of Western culture.  Unfortunately, Socrates left no writings.  His student, Plato, and a colleague, Artistophanes, are credited with accumulating the wisdom of Socrates which may be best described by the Socratic method: observe and understand cause and effect.

Aristotle, a Greek who lived in 3rd century BCE Greece, studied the Socratic method and is often attributed as one of the first to describe how cultural norms were defined.  Aristotle's writings describe a wide range of natural phenomena including those now covered by physics, biology and other natural science.  In observing the phenomena of the natural world, Aristotle described all facets of intellectual inquiry, reasoning, ethics, and politics, which included the study of arts, physics, mathematics and metaphysics.  These writing evolved into the field known as Aristotelian thought which articulate the logic or reason for thought broken down into the most fundamental of questions - (what or why) causes change?  He defined these as: 1) what is the material cause of change? 2) what is the form of change? 3) what is the basis for the efficiency of change? and 4) what is the purpose of change?

Aristarcus (310-230 BCE) proposed that man was nothing more than an ordinary inhabitant of earth, not the center of the universe, based on a complex geometric analysis of the size of the earth's shadow on the moon during an eclipse. He concluded that the sun was much large than the earth, which lead him to the conclusion that smaller objects must revolve around large objects.  Despite failure of the general population to accept this theory, the flat earth concept was disproved 2,600 year ago.  It took another 2,100 years (Copernicus in 1503 AD) to revive this concept.  In 1615, Galileo (1564-1642 AD) endorsed Copernicus' observation which lead to 100+ years of public argument opposing this concept.   In 1515 AD, the Church brought an Inquisition against Galileo for endorsing the concept.  900 years later, the Church has never refuted the Inquisition, stating that the Church is not in the business of confirming scientific findings, forgetting that the Church disparaged and punished Galileo for his scientific beliefs which ultimately were proven beyond a shadow of any doubt to be correct. Later on, Archimedes (287-2121 bc) articulated the law of levers - a long lever can lift a large weight dependent upon where the fulcrum is placed on the lever.

In the 1st century BCE Confucius taught the superiority of personal exemplification over explicit rules of behavior. His moral teachings emphasized self-cultivation, emulation of moral exemplars, and the attainment of skilled judgment rather than knowledge of rules, later to be known as virtue ethics.

Since the times of these early philosophers, many individuals have studied and commented on culture.  Individuals attributed to have major impact on Western culture, in my opinion, include (but are not limited to): Anaximander (610-546 BCE), Pythagoras (580-490 BCE), Confucius (571-479 BCE ), Cicero (106-433 BCE), Augustine of Hippo (354-430 AD), Thomas Aquinas (1225-1274 AD), Nicolas Copernicus (1473-1543 AD), Niccolo Machiavelli (1469-1527 AD), Johannes Kepler (1571-1630 AD), Galileo Galilei (1564-1642 AD), Thomas Hobbs (1588-1679 AD), Rene Descartes (1596-1650 AD), Voltaire - born as François-Marie Arouet (1694-1778 AD), John Locke (1588-1679 AD), Isaac Newton (1643-1727 AD), David Hume (1711-1776 AD), Immanual Kant (1724-1804 AD), Soren Kierkegaard (1813-1855 AD), Karl Marx (1818—1883 AD), Friedrich Nietzche (1844-1900 AD), and Bertrand Russell (1872-1970 AD), are some of the most important.  Their core philosophies are summarized below.

Cicero was known for the beauty of his language and his avid support for the basic tenets of democracy: citizen participation, equality, tolerance, accountability, and transparency.  His thoughts and writings are said to have inspired the Founding Fathers of the United States and the revolutionaries of the French Revolution.   John Adams said, "As all the ages of the world have not produced a greater statesman and philosopher united than Cicero, his authority should have great weight.” Thomas Jefferson names Cicero as one of a handful of major figures who contributed to a tradition "of public right" that informed his draft of the Declaration of Independence and shaped American understandings of "the common sense" basis for the right of revolution.  It is said of the French republicans in 1789 that they were mostly young people who, nourished by the reading of Cicero at school, had become passionate enthusiasts for liberty.

Augustine of Hippolito (aka St Augustine) believed the human being as a perfect unity of soul and body; to be a human is to be a composite of soul and body, with the soul superior to the body.  Augustine taught that God orders all things while preserving human freedom.  Augustine asserted Christians should be pacifists as a personal, philosophical stance.  However, peacefulness in the face of a grave wrong that could only be stopped by violence would be a sin. Defense of one's self or others could be a necessity, especially when authorized by a legitimate authority.   Augustine was among the earliest to examine the legitimacy of the laws of man, and attempt to define the boundaries of what laws and rights occur naturally, instead of being arbitrarily imposed by mortals. All who have wisdom and conscience, he concludes, are able to use reason to recognize natural law (an early mention of natural law).

Through the Dark Ages, that period of many centuries when Western thought was suppressed, Eastern cultures (residing in the region East of Greece to India) blossomed, creating a vast knowledge base in mathematics, physiology, culture, medicine, and religion.  Unfortunately, that explosion of knowledge has been lost during the more recent period when Islam fought to overtake those regions, destroying all aspects of the culture including records of that vast knowledge base in the process.  During the Dark Ages, all logic developed during the era of Greek wisdom described above was suppressed.  Consideration of the laws of nature created by the Greeks faded away as religions of all types and quirks prevailed.  Rules on human conduct prevailed dominated by veneration of God and obedience to rulers, elders, and Church representatives.

Around the 12th century AD, a new era of inquiry was initiated by individuals such as the Christian philosopher Thomas Aquinas (1225-1274 AD) who adopted a view supporting the existence of God by suggesting that human intellect could understand that everything in nature was ruled by a set of laws that could only have been created by an intelligent being known at that time as God. 

Thomas Aquinas' master principle of natural law was that "good is to be done and pursued and evil avoided." Aquinas stated that reason reveals particular natural laws that are good for humans such as self-preservation, marriage and family, and the desire to know God.  Aquinas had respect for Aristotle, so much so that in the Summa, he often cites Aristotle simply as "the Philosopher", a designation frequently used at that time. However, Thomas "never compromised Christian doctrine by bringing it into line with current Aristotelianism; rather, he modified and corrected the latter whenever it clashed with Christian belief”.  Much of Thomas's work influenced subsequent Christian theology, especially that of the Catholic Church, extending to Western philosophy in general.

Aquinas asserts that Christians have a duty to distribute with provision to the poorest of society.  "Social justice" was his term for the reality Thomas Aquinas called "legal justice" or "general justice." Legal or social justice is the contribution from the individual to the common good. So for Aquinas, distributive justice goes in the direction from the common good to the individual, and is a proportional distribution of common goods, to individuals based on their contribution to the community. Legal or general justice, or what came to be called social justice, goes in the other direction, from the individuals to the common good.

It is helpful to understand other related types of justice: if social justice is from the individual to the community, and distributive justice is from the community to the individual, there is also commutative justice (between two individuals, as in buying and selling, or stealing and returning) as well as retributive justice (rectifications that occur to restore justice, once justice has been violated).

A modern concept of the laws of nature emerged in the 17th century articulated by philosophers/scientists of that time such as Galileo (1564-1642), Renee Descartes (1596-1650) and Isaac Newton (1643-1727) who introduced the concept of "science", the use of repetitive physical observation as described by Aristotle who advocated for understanding that repetitive observations of the same action can be used to create predictions of events; these eventually in the 17th century became the laws of nature, events that occur by virtue of nature, not by some inanimate objects mind-process (since they do not have a mind). These laws of nature are exemplified by Newton's law of gravity and the laws of motion; objects in motion stay in motion unless opposed by an opposite motion.  

Nicolas Copernicus (1473-1543 AD), not often considered a philosopher, revolutionized the concept of the universe as not revolving around the earth as the Catholic Church professed, but rather revolving around the sun.  This initiated the process requiring re-thinking of the role of man in nature. 

Niccolo Machiavelli (1469-1527 AD) is sometimes seen as the prototype of a modern empirical scientist, building generalizations from experience and historical facts, and emphasizing the uselessness of theorizing with the imagination.  Machiavelli studied the way people lived and aimed to inform leaders how they should rule and even how they themselves should live. Machiavelli denies the classical opinion that living virtuously always leads to happiness. In much of Machiavelli's work, he often states that the ruler must adopt unsavory policies for the sake of the continuance of his regime.

Machiavelli is generally seen as being critical of Christianity as it existed in his time, specifically its effect upon politics, and also everyday life.  In his opinion, Christianity, along with the teleological Aristotelianism that the Church had come to accept, allowed practical decisions to be guided too much by imaginary ideals and encouraged people to lazily leave events up to providence or, as he would put it, chance, luck or fortune. While Christianity sees modesty as a virtue and pride as sinful, Machiavelli took a more classical position, seeing ambition, spiritedness, and the pursuit of glory as good and natural things, and part of the virtue and prudence that good princes should have.

Rene Descartes (1596-1650 AD) offered a fundamental set of principles that one can know as true without any doubt. To achieve this, he employs a method called hyperbolical/metaphysical doubt; he rejects any ideas that can be doubted, and then re-establishes them in order to acquire a firm foundation for genuine knowledge.  His fundamental principle is "I think, therefore I am”.  Descartes concluded, if he doubted, then something or someone must be doing the doubting; therefore, the very fact that he doubted proved his existence.  According to Descartes, two substances are really distinct when each of them can exist apart from the other. Descartes theories were described by his “Dualism of the mind” principle; he reasoned that God is distinct from humans, and the body and mind of a human are also distinct from one another.  Descartes was also a scientist who introduced the concept of mechanical philosophy suggesting that the physical world consisted of inert particles of matter interacting and colliding with each other.  initiated the evolution of the laws of motion with the particles identified as corpuscles that held the key to understanding the stricture of the universe.

Johannes Kepler (1571-1630 AD), also a scientist, and Galileo Galilei, expanded the work of Copernicus and Descartes to revolutionize the understanding of the universe.  Galileo’s publication of the Mathematical Principles of Natural Philosophy resulted in a deep understanding of the nature of the universe and the role of man in nature.

Copernicus, Descartes, Kepler, Galileo, and others  launched the era of the Renaissance, introducing the concept of science into public perspective, turning the teachings of the Catholic Church entirely upside down.

Voltaire (François-Marie Arouet, 1694-1778 AD) was a deist; he challenged orthodoxy by asking: "What is faith? Is it to believe that which is evident? No. It is perfectly evident to my mind that there exists a necessary, eternal, supreme, and intelligent being. This is no matter of faith, but of reason.”  Voltaire supported the toleration of other religions and ethnicities: "It does not require great art, or magnificently trained eloquence, to prove that Christians should tolerate each other. I, however, am going further: I say that we should regard all men as our brothers. What? The Turk my brother? The Chinaman my brother? The Jew? The Siam? Yes, without doubt; are we not all children of the same father and creatures of the same God?”

Thomas Hobbs (1588-1679 AD) proposed a mechanistic understanding of human beings and their passions, postulating what life would be like without government, a condition which he calls the state of nature.  In that state, each person would have a right, or license, to everything in the world. This, Hobbes argues, would lead to a "war of all against all". The description contains what has been called one of the best-known passages in English philosophy, which describes the natural state humankind would be in, were it not for political community: In such condition, there is no place for industry; because the fruit thereof is uncertain: and consequently no culture of the earth; no navigation, nor use of the commodities that may be imported by sea; no commodious building; no instruments of moving, and removing, such things as require much force; no knowledge of the face of the earth; no account of time; no arts; no letters; no society; and which is worst of all, continual fear, and danger of violent death; and the life of man, solitary, poor, nasty, brutish, and short.

John Locke (1588-1679 AD) exercised profound influence on political philosophy, in particular on modern liberalism.  Locke launched liberalism by tempering Hobbesian absolutism and clearly separating the realms of Church and State. He had a strong influence on Voltaire. His arguments concerning liberty and the social contract later influenced the written works of Alexander Hamilton, James Madison, Thomas Jefferson, and other Founding Fathers of the United States. One passage from the  Locke’s Second Treatise is reproduced verbatim in the Declaration of Independence.

Locke formulated a classic reasoning for religious tolerance in which three arguments are central:

1. Earthly judges, the state in particular, and human beings generally, cannot dependably evaluate the truth-claims of competing religious standpoints;

2. Even if they could, enforcing a single 'true religion' would not have the desired effect, because belief cannot be compelled by violence;

3. Coercing religious uniformity would lead to more social disorder than allowing diversity.

David Hume (1711-1776 AD) stated that the mind consists of perceptions, or the mental objects which are present to it, and which divide into two categories: impressions and ideas. Hume believed this to mean the distinction between feeling and thinking.  Hume regarded this distinction as a matter of degree, as he takes impressions to be distinguished from ideas on the basis of their force, liveliness, and vivacity.   Ideas are therefore "faint" impressions. For example, experiencing the painful sensation of touching a hot pan's handle is more forceful than simply thinking about touching a hot pan. According to Hume, impressions are meant to be the original form of all our ideas; all ideas are ultimately copied from some original impression, whether it be a passion or sensation, from which they derive.

Immanual Kant (1724-1804 AD) was greatly impressed with the scientific advances made by Newton and others. This new evidence of the power of human reason, however, called into question the traditional authority of politics and religion. Although this was in some respects liberating, it was in other respects threatening. In particular, the modern mechanistic view of the world called into question the very possibility of morality; for, if there is no agency, there cannot be any responsibility.

Kant's treatise was that evolution served to secure human autonomy, the basis of religion and morality, from the threat of mechanistic view—and to do so in a way that preserves the advances of modern science.

In his Critique of Pure Reason, Kant summarizes his philosophical concerns in the following three questions:

1. What can I know?  2. What should I do?  3. What may I hope?

Kants thesis states that human beings only experience and know appearances, not things-in-themselves, because space and time are nothing but the subjective forms of intuition that we ourselves contribute to experience.

Kant posits that we are not able to transcend the bounds of our own mind, meaning that we cannot access the "thing-in-itself." However, Kant also speaks of the thing in itself or transcendent object as a product of the (human) understanding as it attempts to conceive of objects in abstraction from the conditions of sensibility. Following this line of thought, some interpreters have argued that the thing in itself does not represent a separate ontological domain but simply a way of considering objects by means of the understanding alone—this is known as the "two-aspect" view.

Soren Kierkegaard (1813-1855 AD) has been called a philosopher, a theologian, the Father of Existentialism, a literary critic, a social theorist, a humorist, a psychologist, and a poet.  Two of his influential ideas are “subjectivity", and the notion popularly referred to as "leap of faith”.   However, the Danish equivalent to the English phrase "leap of faith" does not appear in the original Danish nor is the English phrase found in current English translations of Kierkegaard's works. Kierkegaard does mention the concepts of "faith" and "leap" together many times in his works.

The leap of faith is the conception of how an individual would believe in God or how a person would act in love. Faith is not a decision based on evidence that certain beliefs about God are true or a certain person is worthy of love. No such evidence could ever be enough to completely justify the kind of total commitment involved in true religious faith or romantic love. Faith involves making that commitment anyway. Kierkegaard thought that to have faith is at the same time to have doubt. So, for example, for one to truly have faith in God, one would also have to doubt one's beliefs about God; the doubt is the rational part of a person's thought involved in weighing evidence, without which the faith would have no real substance. Someone who does not realize that Christian doctrine is inherently doubtful and that there can be no objective certainty about its truth does not have faith but is merely credulous. For example, it takes no faith to believe that a pencil or a table exists, when one is looking at it and touching it. In the same way, to believe or have faith in God is to know that one has no perceptual or any other access to God, and yet still has faith in God.

Kierkegaard also stressed the importance of the self, and the self's relation to the world, as being grounded in self-reflection and introspection. He argued that "subjectivity is truth" and "truth is subjectivity." This has to do with a distinction between what is objectively true and an individual's subjective relation (such as indifference or commitment) to that truth. People who in some sense believe the same things may relate to those beliefs quite differently. Two individuals may both believe that many of those around them are poor and deserve help, but this knowledge may lead only one of them to decide to actually help the poor.

Karl Marx (1818—1883 AD) set out to analyze "the despotism of capital”.  Fundamentally, Marx assumed that human history involves transforming human nature, which encompasses both human beings and material object.  Humans recognize that they possess both actual and potential selves.  He states "the fact that man is a corporeal, actual, sentient, objective being with natural capacities means that he has actual, sensuous objects for his nature as objects of his life-expression, or that he can only express his life in actual sensuous objects”.

Marx had a special concern with how people relate to their own labour power.  He wrote extensively about this in terms of the problem of alienation. Marx began with a Hegelian notion of alienation but developed a more materialist conception.  Capitalism mediates social relationships of production (such as among workers or between workers and capitalists) through commodities, including labour, that are bought and sold on the market.  For Marx, the possibility that one may give up ownership of one's own labour – one's capacity to transform the world – is tantamount to being alienated from one's own nature and it is a spiritual loss.  Marx described this loss as commodity fetishism, in which the things that people produce, commodities, appear to have a life and movement of their own to which humans and their behavior merely adapt.

Friedrich Nietzche (1844-1900 AD) founded his thoughts on the study of two figures in ancient Greek mythology, Apollo and Dionysus. The relationship is described in a debate between the two defined by the Apollonian perspective and the Dionysian perspective; the Apollonian a dreaming state, full of illusions; and Dionysian a state of intoxication, representing the liberations of instinct and dissolution of boundaries.  In this debate, a satyr appears representing the annihilation of the principle of individuality. These principles are meant to represent cognitive states that appear through art as the power of nature in man.  Greek spectators, by looking into the abyss of human suffering depicted by these characters, passionately and joyously affirmed life, finding it worth living. Nietzsche found in classical Athenian tragedy an art form that transcended pessimism.

The main theme in The Birth of Tragedy is that the fusion of Dionysian and Apollonian Kunsttriebe ("artistic impulses") forms dramatic arts or tragedies.  This lead Nietzche to support existentialism, the philosophical belief that we are each responsible for creating purpose or meaning in our own lives. Individual purpose and meaning is not given to us by Gods, governments, teachers or other authorities.  Existentialist philosophers explore questions related to the meaning, purpose, and value of human existence. Common concepts in existentialist thought include existential crisis, dread, and anxiety in the face of an absurd world, as well as authenticity, courage, and virtue. He is famous for uncompromising criticisms of traditional European morality and religion, as well as of conventional philosophical ideas and social and political pieties associated with modernity. Many of these criticisms rely on psychological diagnoses that expose false consciousness infecting people’s received ideas; for that reason, he is often associated with a group of late modern thinkers (including Marx and Freud) who advanced a “hermeneutics of suspicion” against traditional values. Nietzsche also used his psychological analyses to support original theories about the nature of the self and provocative proposals suggesting new values that he thought would promote cultural renewal and improve social and psychological life by comparison to life under the traditional values he criticized.

Bertrand Russell (1872-1970 AD) is generally credited with being one of the founders of analytic philosophy.  He was particularly prolific in the fields of metaphysics, logic and the philosophy of mathematics, the philosophy of language, ethics and epistemology. For the advancement of science and protection of liberty of expression, Russell advocated the will to doubt, the recognition that all human knowledge is at most a best guess, that one should always remember:  None of our beliefs are quite true; all have at least a penumbra of vagueness and error. The methods of increasing the degree of truth in our beliefs are well known; they consist in hearing all sides, trying to ascertain all the relevant facts, controlling our own bias by discussion with people who have the opposite bias, and cultivating a readiness to discard any hypothesis which has proved inadequate. These methods are practiced in science, and have built up the body of scientific knowledge. Every man of science whose outlook is truly scientific is ready to admit that what passes for scientific knowledge at the moment is sure to require correction with the progress of discovery; nevertheless, it is near enough to the truth to serve for most practical purposes, though not for all. In science, where alone something approximating to genuine knowledge is to be found, men's attitude is tentative and full of doubt.

Russell described himself as an agnostic or an atheist.  He found it difficult to determine which term to adopt, saying: “In regard to the Olympic gods, speaking to a purely philosophical audience, I would say that I am an Agnostic. But speaking popularly, I think that all of us would say in regard to those gods that we were Atheists. In regard to the Christian God, I should, I think, take exactly the same line”.  For most of his adult life, Russell maintained religion to be little more than superstition and, despite any positive effects, largely harmful to people.

Thoughts attributed to these philosophers:

Socrates- observe and understand cause and effect.

Aritstotle- articulate the logic or reason for thought broken down into the most fundamental of questions - (what or why) causes change?

Confucius- personal exemplification over explicit rules of behavior.

Cicero- citizen participation, equality, tolerance, accountability, and transparency.

Hippolito- human being is the perfect unity of soul and body.

Aquinas- good is to be done and pursued and evil avoided.

Machiavelli- inform leaders how they should rule and even how they themselves should live.   the ruler may adopt unsavory policies for the sake of the continuance of his regime.   Christianity and Aristotelianism allowed decisions to be guided too much by imaginary ideals and encouraged people to (lazily) leave events up to providence.

Descartes- reject any ideas that can be doubted, and then reacquire them in order to create a firm foundation for genuine knowledge.

Voltaire- there exists a necessary, eternal, supreme, and intelligent being which requires toleration of other religions and ethnicities.

Hobbs- the natural state for humankind is the political community.  In such condition, there is no place for industry; because the fruit thereof is uncertain.

Locke- modern liberalism clearly separates the realms of Church and State.

Hume- mind consists of perceptions creating distinction between feeling and thinking.

Kant - the power of human reason calls into question the traditional authority of politics and religion.

Kierkegard and Nietzche-  we are each responsible for creating purpose or meaning in our own lives.  Individual purpose and meaning is not given to us by Gods, governments, teachers or other authorities.

Marx-  people own their labour efforts.

Russell- one should always remember that humans possess the will to doubt.  Human knowledge is at most a best guess.